WorldWideScience

Sample records for 3-d thermal evaluations

  1. Evaluation of novel Ti-doped 3D carbon-carbon composites under transient thermal loads

    Centeno, A. [Instituto Nacional del Carbon (CSIC), Apdo. 73, 33080-Oviedo (Spain); Blanco, C., E-mail: clara@incar.csic.e [Instituto Nacional del Carbon (CSIC), Apdo. 73, 33080-Oviedo (Spain); Santamaria, R.; Granda, M.; Menendez, R. [Instituto Nacional del Carbon (CSIC), Apdo. 73, 33080-Oviedo (Spain); Pintsuk, G.; Linke, J. [Forschungszentrum Juelich GmbH, EURATOM Association, 52425-Juelich (Germany)

    2010-08-15

    3D Ti-doped and undoped carbon-carbon composites (CFCs) were exposed to transient thermal loads to simulate plasma disruptions, in the electron beam test facility JUDITH at different power densities and multiple shots in order to study the evolution in the behavior of the material. The thermal shock response of the undoped and Ti-doped materials was compared in order to study the influence of titanium carbide as dopant. The erosion itself is driven during the first shots by macroscopic erosion (brittle destruction), which is a result of thermally induced stresses. With increasing number of shots, no more brittle destruction is observed and the main erosion mechanism is sublimation due to local overheating. This is also confirmed by the decrease of the erosion rate with increasing the number of shots. The pitch fibers are hardly affected by the applied heat loads and they show almost no erosion, especially in the Ti-doped composite.

  2. Evaluation of Methods for Coregistration and Fusion of Rpas-Based 3d Point Clouds and Thermal Infrared Images

    Hoegner, L.; Tuttas, S.; Xu, Y.; Eder, K.; Stilla, U.

    2016-06-01

    This paper discusses the automatic coregistration and fusion of 3d point clouds generated from aerial image sequences and corresponding thermal infrared (TIR) images. Both RGB and TIR images have been taken from a RPAS platform with a predefined flight path where every RGB image has a corresponding TIR image taken from the same position and with the same orientation with respect to the accuracy of the RPAS system and the inertial measurement unit. To remove remaining differences in the exterior orientation, different strategies for coregistering RGB and TIR images are discussed: (i) coregistration based on 2D line segments for every single TIR image and the corresponding RGB image. This method implies a mainly planar scene to avoid mismatches; (ii) coregistration of both the dense 3D point clouds from RGB images and from TIR images by coregistering 2D image projections of both point clouds; (iii) coregistration based on 2D line segments in every single TIR image and 3D line segments extracted from intersections of planes fitted in the segmented dense 3D point cloud; (iv) coregistration of both the dense 3D point clouds from RGB images and from TIR images using both ICP and an adapted version based on corresponding segmented planes; (v) coregistration of both image sets based on point features. The quality is measured by comparing the differences of the back projection of homologous points in both corrected RGB and TIR images.

  3. 3D Multifunctional Ablative Thermal Protection System

    Feldman, Jay; Venkatapathy, Ethiraj; Wilkinson, Curt; Mercer, Ken

    2015-01-01

    NASA is developing the Orion spacecraft to carry astronauts farther into the solar system than ever before, with human exploration of Mars as its ultimate goal. One of the technologies required to enable this advanced, Apollo-shaped capsule is a 3-dimensional quartz fiber composite for the vehicle's compression pad. During its mission, the compression pad serves first as a structural component and later as an ablative heat shield, partially consumed on Earth re-entry. This presentation will summarize the development of a new 3D quartz cyanate ester composite material, 3-Dimensional Multifunctional Ablative Thermal Protection System (3D-MAT), designed to meet the mission requirements for the Orion compression pad. Manufacturing development, aerothermal (arc-jet) testing, structural performance, and the overall status of material development for the 2018 EM-1 flight test will be discussed.

  4. Dynamics of 3D isolated thermal filaments

    Walkden, N R; Militello, F; Omotani, J T

    2016-01-01

    Simulations have been carried out to establish how electron thermal physics, introduced in the form of a dynamic electron temperature, affects isolated filament motion and dynamics in 3D. It is found that thermal effects impact filament motion in two major ways when the filament has a significant temperature perturbation compared to its density perturbation: They lead to a strong increase in filament propagation in the bi-normal direction and a significant decrease in net radial propagation. Both effects arise from the temperature dependence of the sheath current which leads to a non-uniform floating potential, with the latter effect supplemented by faster pressure loss. The reduction in radial velocity can only occur when the filament cross-section loses angular symmetry. The behaviour is observed across different filament sizes and suggests that filaments with much larger temperature perturbations than density perturbations are more strongly confined to the near SOL region.

  5. Dynamics of 3D isolated thermal filaments

    Walkden, N. R.; Easy, L.; Militello, F.; Omotani, J. T.

    2016-11-01

    Simulations have been carried out to establish how electron thermal physics, introduced in the form of a dynamic electron temperature, affects isolated filament motion and dynamics in 3D. It is found that thermal effects impact filament motion in two major ways when the pressure perturbation within the filament is supported primarily through a temperature increase as opposed to density: they lead to a strong increase in filament propagation in the bi-normal direction and a significant decrease in net radial propagation. Both effects arise from the temperature dependence of the sheath current which leads to a non-uniform floating potential, with the latter effect supplemented by faster pressure loss. The reduction in radial velocity can only occur when the filament cross-section loses angular symmetry. The behaviour is observed across different filament sizes and suggests that filaments with much larger temperature perturbations than density perturbations are more strongly confined to the near SOL region.

  6. 3D SURFACE GENERATION FROM AERIAL THERMAL IMAGERY

    B. Khodaei

    2015-12-01

    Full Text Available Aerial thermal imagery has been recently applied to quantitative analysis of several scenes. For the mapping purpose based on aerial thermal imagery, high accuracy photogrammetric process is necessary. However, due to low geometric resolution and low contrast of thermal imaging sensors, there are some challenges in precise 3D measurement of objects. In this paper the potential of thermal video in 3D surface generation is evaluated. In the pre-processing step, thermal camera is geometrically calibrated using a calibration grid based on emissivity differences between the background and the targets. Then, Digital Surface Model (DSM generation from thermal video imagery is performed in four steps. Initially, frames are extracted from video, then tie points are generated by Scale-Invariant Feature Transform (SIFT algorithm. Bundle adjustment is then applied and the camera position and orientation parameters are determined. Finally, multi-resolution dense image matching algorithm is used to create 3D point cloud of the scene. Potential of the proposed method is evaluated based on thermal imaging cover an industrial area. The thermal camera has 640×480 Uncooled Focal Plane Array (UFPA sensor, equipped with a 25 mm lens which mounted in the Unmanned Aerial Vehicle (UAV. The obtained results show the comparable accuracy of 3D model generated based on thermal images with respect to DSM generated from visible images, however thermal based DSM is somehow smoother with lower level of texture. Comparing the generated DSM with the 9 measured GCPs in the area shows the Root Mean Square Error (RMSE value is smaller than 5 decimetres in both X and Y directions and 1.6 meters for the Z direction.

  7. Multimodal Registration and Fusion for 3D Thermal Imaging

    Moulay A. Akhloufi

    2015-01-01

    Full Text Available 3D vision is an area of computer vision that has attracted a lot of research interest and has been widely studied. In recent years we witness an increasing interest from the industrial community. This interest is driven by the recent advances in 3D technologies, which enable high precision measurements at an affordable cost. With 3D vision techniques we can conduct advanced manufactured parts inspections and metrology analysis. However, we are not able to detect subsurface defects. This kind of detection is achieved by other techniques, like infrared thermography. In this work, we present a new registration framework for 3D and thermal infrared multimodal fusion. The resulting fused data can be used for advanced 3D inspection in Nondestructive Testing and Evaluation (NDT&E applications. The fusion permits the simultaneous visible surface and subsurface inspections to be conducted in the same process. Experimental tests were conducted with different materials. The obtained results are promising and show how these new techniques can be used efficiently in a combined NDT&E-Metrology analysis of manufactured parts, in areas such as aerospace and automotive.

  8. Thermal Protection System Materials (TPSM): 3D MAT Project

    National Aeronautics and Space Administration — The 3D MAT Project seeks to design and develop a game changing Woven Thermal Protection System (TPS) technology tailored to meet the needs of the Orion Multi-Purpose...

  9. Evaluation of the thermal and hydraulic performances of a very thin sintered copper flat heat pipe for 3D microsystem packages

    Tzanova, S; Avenas, Y; Schaeffer, Ch

    2008-01-01

    The reported research work presents numerical studies validated by experimental results of a flat micro heat pipe with sintered copper wick structure. The objectives of this project are to produce and demonstrate the efficiency of the passive cooling technology (heat pipe) integrated in a very thin electronic substrate that is a part of a multifunctional 3-D electronic package. The enhanced technology is dedicated to the thermal management of high dissipative microsystems having heat densities of more than 10W/cm2. Future applications are envisaged in the avionics sector. In this research 2D numerical hydraulic model has been developed to investigate the performance of a very thin flat micro heat pipe with sintered copper wick structure, using water as a refrigerant. Finite difference method has been used to develop the model. The model has been used to determine the mass transfer and fluid flow in order to evaluate the limits of heat transport capacity as functions of the dimensions of the wick and the vapou...

  10. Reduction of thermal conductivity by nanoscale 3D phononic crystal.

    Yang, Lina; Yang, Nuo; Li, Baowen

    2013-01-01

    We studied how the period length and the mass ratio affect the thermal conductivity of isotopic nanoscale three-dimensional (3D) phononic crystal of Si. Simulation results by equilibrium molecular dynamics show isotopic nanoscale 3D phononic crystals can significantly reduce the thermal conductivity of bulk Si at high temperature (1000 K), which leads to a larger ZT than unity. The thermal conductivity decreases as the period length and mass ratio increases. The phonon dispersion curves show an obvious decrease of group velocities in 3D phononic crystals. The phonon's localization and band gap is also clearly observed in spectra of normalized inverse participation ratio in nanoscale 3D phononic crystal.

  11. 3D shape measurement with thermal pattern projection

    Brahm, Anika; Reetz, Edgar; Schindwolf, Simon; Correns, Martin; Kühmstedt, Peter; Notni, Gunther

    2016-12-01

    Structured light projection techniques are well-established optical methods for contactless and nondestructive three-dimensional (3D) measurements. Most systems operate in the visible wavelength range (VIS) due to commercially available projection and detection technology. For example, the 3D reconstruction can be done with a stereo-vision setup by finding corresponding pixels in both cameras followed by triangulation. Problems occur, if the properties of object materials disturb the measurements, which are based on the measurement of diffuse light reflections. For example, there are existing materials in the VIS range that are too transparent, translucent, high absorbent, or reflective and cannot be recorded properly. To overcome these challenges, we present an alternative thermal approach that operates in the infrared (IR) region of the electromagnetic spectrum. For this purpose, we used two cooled mid-wave (MWIR) cameras (3-5 μm) to detect emitted heat patterns, which were introduced by a CO2 laser. We present a thermal 3D system based on a GOBO (GOes Before Optics) wheel projection unit and first 3D analyses for different system parameters and samples. We also show a second alternative approach based on an incoherent (heat) source, to overcome typical disadvantages of high-power laser-based systems, such as industrial health and safety considerations, as well as high investment costs. Thus, materials like glass or fiber-reinforced composites can be measured contactless and without the need of additional paintings.

  12. Creating 3D gelatin phantoms for experimental evaluation in biomedicine

    Stein Nils

    2015-09-01

    Full Text Available We describe and evaluate a setup to create gelatin phantoms by robotic 3D printing. Key aspects are the large workspace, reproducibility and resolution of the created phantoms. Given its soft tissue nature, the gelatin is kept fluid during inside the system and we present parameters for additive printing of homogeneous, solid objects. The results indicate that 3D printing of gelatin can be an alternative for quickly creating larger soft tissue phantoms without the need for casting a mold.

  13. Performance Evaluation of 3d Modeling Software for Uav Photogrammetry

    Yanagi, H.; Chikatsu, H.

    2016-06-01

    UAV (Unmanned Aerial Vehicle) photogrammetry, which combines UAV and freely available internet-based 3D modeling software, is widely used as a low-cost and user-friendly photogrammetry technique in the fields such as remote sensing and geosciences. In UAV photogrammetry, only the platform used in conventional aerial photogrammetry is changed. Consequently, 3D modeling software contributes significantly to its expansion. However, the algorithms of the 3D modelling software are black box algorithms. As a result, only a few studies have been able to evaluate their accuracy using 3D coordinate check points. With this motive, Smart3DCapture and Pix4Dmapper were downloaded from the Internet and commercial software PhotoScan was also employed; investigations were performed in this paper using check points and images obtained from UAV.

  14. An Evaluative Review of Simulated Dynamic Smart 3d Objects

    Romeijn, H.; Sheth, F.; Pettit, C. J.

    2012-07-01

    Three-dimensional (3D) modelling of plants can be an asset for creating agricultural based visualisation products. The continuum of 3D plants models ranges from static to dynamic objects, also known as smart 3D objects. There is an increasing requirement for smarter simulated 3D objects that are attributed mathematically and/or from biological inputs. A systematic approach to plant simulation offers significant advantages to applications in agricultural research, particularly in simulating plant behaviour and the influences of external environmental factors. This approach of 3D plant object visualisation is primarily evident from the visualisation of plants using photographed billboarded images, to more advanced procedural models that come closer to simulating realistic virtual plants. However, few programs model physical reactions of plants to external factors and even fewer are able to grow plants based on mathematical and/or biological parameters. In this paper, we undertake an evaluation of plant-based object simulation programs currently available, with a focus upon the components and techniques involved in producing these objects. Through an analytical review process we consider the strengths and weaknesses of several program packages, the features and use of these programs and the possible opportunities in deploying these for creating smart 3D plant-based objects to support agricultural research and natural resource management. In creating smart 3D objects the model needs to be informed by both plant physiology and phenology. Expert knowledge will frame the parameters and procedures that will attribute the object and allow the simulation of dynamic virtual plants. Ultimately, biologically smart 3D virtual plants that react to changes within an environment could be an effective medium to visually represent landscapes and communicate land management scenarios and practices to planners and decision-makers.

  15. Thermal and mechanical properties of selected 3D printed thermoplastics in the cryogenic temperature regime

    Weiss, K.-P.; Bagrets, N.; Lange, C.; Goldacker, W.; Wohlgemuth, J.

    2015-12-01

    Insulating materials for use in cryogenic boundary conditions are still limited to a proved selection as Polyamid, Glasfiber reinforced resins, PEEK, Vespel etc. These materials are usually formed to parts by mechanical machining or sometimes by cast methods. Shaping complex geometries in one piece is limited. Innovative 3D printing is now an upcoming revolutionary technology to construct functional parts from a couple of thermoplastic materials as ABS, Nylon and others which possess quite good mechanical stability and allow realizing very complex shapes with very subtle details. Even a wide range of material mixtures is an option and thermal treatments can be used to finish the material structure for higher performance. The use of such materials in cryogenic environment is very attractive but so far poor experience exists. In this paper, first investigations of the thermal conductivity, expansion and mechanical strength are presented for a few selected commercial 3D material samples to evaluate their application prospects in the cryogenic temperature regime.

  16. 3D thermal modeling of TRISO fuel coupled with neutronic simulation

    Hu, Jianwei [Los Alamos National Laboratory; Uddin, Rizwan [UNIV OF ILLINIOS

    2010-01-01

    The Very High Temperature Gas Reactor (VHTR) is widely considered as one of the top candidates identified in the Next Generation Nuclear Power-plant (NGNP) Technology Roadmap under the U.S . Depanment of Energy's Generation IV program. TRlSO particle is a common element among different VHTR designs and its performance is critical to the safety and reliability of the whole reactor. A TRISO particle experiences complex thermo-mechanical changes during reactor operation in high temperature and high burnup conditions. TRISO fuel performance analysis requires evaluation of these changes on micro scale. Since most of these changes are temperature dependent, 3D thermal modeling of TRISO fuel is a crucial step of the whole analysis package. In this paper, a 3D numerical thermal model was developed to calculate temperature distribution inside TRISO and pebble under different scenarios. 3D simulation is required because pebbles or TRISOs are always subjected to asymmetric thermal conditions since they are randomly packed together. The numerical model was developed using finite difference method and it was benchmarked against ID analytical results and also results reported from literature. Monte-Carlo models were set up to calculate radial power density profile. Complex convective boundary condition was applied on the pebble outer surface. Three reactors were simulated using this model to calculate temperature distribution under different power levels. Two asymmetric boundary conditions were applied to the pebble to test the 3D capabilities. A gas bubble was hypothesized inside the TRISO kernel and 3D simulation was also carried out under this scenario. Intuition-coherent results were obtained and reported in this paper.

  17. Development and Evaluation of Gold 3D Cylindrical Nanoelectrode Ensembles

    CAO Li-Xin; YAN Pei-Sheng; SUN Ke-Ning; KIRK W Donald

    2007-01-01

    Gold 3D cylindrical nanoelectrode ensembles (NEEs), 100 nm in diameter and 500 nm in length were prepared by electroless template synthesis in polycarbonate filter membranes, followed by selective controlled chemical etching. The morphology of the nanowires and cylindrical NEEs was imaged by scanning electron microscopy. The protruding nanoelectrodes were in good parallel order. EDX study showed that the nanoelectrode elements consisted of pure gold. The electrochemical evaluation of the 3D electrodes was conducted using the well known [Fe(CN)6]3-/[Fe(CN)6]4- couple. Cyclic voltammgrams (CV) show a very low double layer charging current and a higher ratio of signal to background current than 2D disc NEEs. Electrochemical impedance spectroscopy (EIS) indicates that the 3D cylindrical NEEs effectively accelerate the charge transfer process, which is in consistent with the results of CV. The linear relationship with a slope of 0.5 between lg Ipc and lg v shows that linear diffusion is dominant on the 3D cylindrical NEEs at conventional scan rates.

  18. 3D painting documentation: evaluation of conservation conditions with 3D imaging and ranging techniques

    Abate, D.; Menna, F.; Remondino, F.; Gattari, M. G.

    2014-06-01

    The monitoring of paintings, both on canvas and wooden support, is a crucial issue for the preservation and conservation of this kind of artworks. Many environmental factors (e.g. humidity, temperature, illumination, etc.), as well as bad conservation practices (e.g. wrong restorations, inappropriate locations, etc.), can compromise the material conditions over time and deteriorate an artwork. The article presents an on-going project realized by a multidisciplinary team composed by the ENEA UTICT 3D GraphLab, the 3D Optical Metrology Unit of the Bruno Kessler Foundation and the Soprintendenza per i Beni Storico Artistici ed Etnoantropologici of Bologna (Italy). The goal of the project is the multi-temporal 3D documentation and monitoring of paintings - at the moment in bad conservation's situation - and the provision of some metrics to quantify the deformations and damages.

  19. Design Novel 3D Nano Architectures for Developing Ultra Fast Thermal Energy Storage Materials

    2015-04-30

    AFRL-AFOSR-UK-TR-2015-0036 Design novel 3D nano-architectures for developing ultra fast thermal energy storage materials...ultra fast thermal energy storage materials 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA8655-12-1-2014 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S...ANSI Std. Z39.18 FINAL TECHNICAL REPORT Project Title : Design novel 3D nano-architectures for developing ultra fast thermal energy storage

  20. Subjective evaluation of a 3D videoconferencing system

    Rizek, Hadi; Brunnström, Kjell; Wang, Kun; Andrén, Börje; Johanson, Mathias

    2014-03-01

    A shortcoming of traditional videoconferencing systems is that they present the user with a flat, two-dimensional image of the remote participants. Recent advances in autostereoscopic display technology now make it possible to develop video conferencing systems supporting true binocular depth perception. In this paper, we present a subjective evaluation of a prototype multiview autostereoscopic video conferencing system and suggest a number of possible improvements based on the results. Whereas methods for subjective evaluation of traditional 2D videoconferencing systems are well established, the introduction of 3D requires an extension of the test procedures to assess the quality of depth perception. For this purpose, two depth-based test tasks have been designed and experiments have been conducted with test subjects comparing the 3D system to a conventional 2D video conferencing system. The outcome of the experiments show that the perception of depth is significantly improved in the 3D system, but the overall quality of experience is higher in the 2D system.

  1. Evaluating lubricant performance by 3D profilometry of wear scars

    Georgescu, C.; Deleanu, L.; Pirvu, C.

    2016-08-01

    Due to improvement in analysing surface texture and optical instruments for investigating the texture surface, the authors propose to evaluate the lubricant performance by analysing the change in several 3D parameters in comparison to an analysis on 2D profile. All the surface of the wear scar generated on the four ball machine is investigated and the conclusion is that from the tribological point of view, the 3D parameters reflect better the surface quality evolution after testing. Investigation was done on the wear scars generated on the three fixed balls, for five lubricants: a non-additivated transmission mineral oil (T90), two grades of rapeseed oil (coarse degummed and refined) and two grades of soybean oil (coarse and degummed).

  2. 3D thermal-hydraulic analysis of two irregular field joints for the ITER vacuum vessel

    Savoldi, Laura, E-mail: laura.savoldi@polito.it [Dipartimento Energia, Politecnico di Torino, I-10129 Torino (Italy); Bonifetto, Roberto [Dipartimento Energia, Politecnico di Torino, I-10129 Torino (Italy); Izquierdo, Jesus [Fusion for Energy, ES-08019 Barcelona (Spain); Le Barbier, Robin; Utin, Yuri [ITER Organization, Route de Vinon sur Verdon, CS 90 046, 13067 Saint Paul Lez Durance Cedex (France); Zanino, Roberto [Dipartimento Energia, Politecnico di Torino, I-10129 Torino (Italy)

    2015-10-15

    Highlights: • ITER vacuum vessel irregular field joints analyzed with ANSYS-FLUENT. • Steady-state thermal-hydraulic performance evaluated with 3D analysis. • Pressure drop comparable to that of regular field joints. • Acceptable hot spots on the inner shell and ports. • Heat transfer coefficient above the target value of 500 W/m{sup 2} K on the inner shell. - Abstract: In ITER, so-called “Irregular” Field Joints (IFJs) are foreseen at the interface between irregular sectors of the Vacuum Vessel (VV), which is located inside the cryostat and houses the in-vessel components. In the IFJs, a peculiar design of the equatorial port, with respect to that adopted in the Regular Field Joints (RFJs), accommodates the irregularities of the adjacent VV sectors. The IFJs are subject to nuclear heating and actively cooled by sub-cooled pressurized water flowing in a dedicated hydraulic loop, which includes the space left open by the borated In-Wall Shielding (IWS). Here we perform the 3D steady state thermal-hydraulic analysis of two different IFJs using the Computational Fluid Dynamics (CFD) software ANSYS-FLUENT{sup ®}. The water flow field, the pressure drop and the temperature maps are computed. The thermal performance of the IFJs in nominal operation is compared to that of an RFJ and it is shown that also in this case enough cooling capability is available to avoid hot spots above the design limits, while the pressure drop remains acceptably low.

  3. Study of the thermal properties of filaments for 3D printing

    Trhlíková, Lucie; Zmeskal, Oldrich; Psencik, Petr; Florian, Pavel

    2016-07-01

    Various materials are used for 3D printing, most commonly Acrylonitrile butadiene styrene (ABS), Polylactic acid (PLA), Polyethylene (PET) and Polypropylene (PP). These materials differ mainly in their melting point, which significantly influences the properties of the final products. Filaments are melted in the print head during the printing process. The temperature range is from 150 °C to 250 °C depending on the technology used. The optimum temperature for the cooling substrate on which printing is carried out is chosen so as to ensure uniform cooling and deformation. It generally varies between (40 - 100) °C. From the above it is clear that both temperatures can significantly affect the properties of the printed 3D object. It is therefore important to determine the thermal parameters (thermal conductivity, specific heat and thermal diffusivity) of the materials used across the entire range of temperatures. For evaluating the properties of different types of PLA materials, the step transient method was used, which allows determination of all required parameters using a fractal heat transfer model.

  4. 3D Printing Fabrication of Amorphous Thermoelectric Materials with Ultralow Thermal Conductivity.

    He, Minhong; Zhao, Yan; Wang, Biao; Xi, Qing; Zhou, Jun; Liang, Ziqi

    2015-11-25

    Thermoelectric materials are prepared by developing 3D printing technology. The 3D fabricated Bi0.5 Sb1.5 Te3 samples exhibit amorphous characteristics and thus show an ultralow thermal conductivity of 0.2 W m(-1) K(-1) . 3D printing fabrication readily generates bulk thermoelectric samples of any shape, which is not the case with traditional hot-pressing and spark plasma sintering methods.

  5. Evaluation of Kinect 3D Sensor for Healthcare Imaging.

    Pöhlmann, Stefanie T L; Harkness, Elaine F; Taylor, Christopher J; Astley, Susan M

    2016-01-01

    Microsoft Kinect is a three-dimensional (3D) sensor originally designed for gaming that has received growing interest as a cost-effective and safe device for healthcare imaging. Recent applications of Kinect in health monitoring, screening, rehabilitation, assistance systems, and intervention support are reviewed here. The suitability of available technologies for healthcare imaging applications is assessed. The performance of Kinect I, based on structured light technology, is compared with that of the more recent Kinect II, which uses time-of-flight measurement, under conditions relevant to healthcare applications. The accuracy, precision, and resolution of 3D images generated with Kinect I and Kinect II are evaluated using flat cardboard models representing different skin colors (pale, medium, and dark) at distances ranging from 0.5 to 1.2 m and measurement angles of up to 75°. Both sensors demonstrated high accuracy (majority of measurements Kinect I is capable of imaging at shorter measurement distances, but Kinect II enables structures angled at over 60° to be evaluated. Kinect II showed significantly higher precision and Kinect I showed significantly higher resolution (both p Kinect is not a medical imaging device, both sensor generations show performance adequate for a range of healthcare imaging applications. Kinect I is more appropriate for short-range imaging and Kinect II is more appropriate for imaging highly curved surfaces such as the face or breast.

  6. 3D thermal medical image visualization tool: Integration between MRI and thermographic images.

    Abreu de Souza, Mauren; Chagas Paz, André Augusto; Sanches, Ionildo Jóse; Nohama, Percy; Gamba, Humberto Remigio

    2014-01-01

    Three-dimensional medical image reconstruction using different images modalities require registration techniques that are, in general, based on the stacking of 2D MRI/CT images slices. In this way, the integration of two different imaging modalities: anatomical (MRI/CT) and physiological information (infrared image), to generate a 3D thermal model, is a new methodology still under development. This paper presents a 3D THERMO interface that provides flexibility for the 3D visualization: it incorporates the DICOM parameters; different color scale palettes at the final 3D model; 3D visualization at different planes of sections; and a filtering option that provides better image visualization. To summarize, the 3D thermographc medical image visualization provides a realistic and precise medical tool. The merging of two different imaging modalities allows better quality and more fidelity, especially for medical applications in which the temperature changes are clinically significant.

  7. ETeach3D: Designing a 3D Virtual Environment for Evaluating the Digital Competence of Preservice Teachers

    Esteve-Mon, Francesc M.; Cela-Ranilla, Jose María; Gisbert-Cervera, Mercè

    2016-01-01

    The acquisition of teacher digital competence is a key aspect in the initial training of teachers. However, most existing evaluation instruments do not provide sufficient evidence of this teaching competence. In this study, we describe the design and development process of a three-dimensional (3D) virtual environment for evaluating the teacher…

  8. Optimisation of trench isolated bipolar transistors on SOI substrates by 3D electro-thermal simulations

    Nigrin, S.; Armstrong, G. A.; Kranti, A.

    2007-09-01

    This paper provides a comprehensive analysis of thermal resistance of trench isolated bipolar transistors on SOI substrates based on 3D electro-thermal simulations calibrated to experimental data. The impact of emitter length, width, spacing and number of emitter fingers on thermal resistance is analysed in detail. The results are used to design and optimise transistors with minimum thermal resistance and minimum transistor area.

  9. Evaluation of 3D Positioned Sound in Multimodal Scenarios

    Møller, Anders Kalsgaard

    present but interacts with the other meeting members using different virtual reality technologies. The thesis also dealt with a 3D sound system in trucks. it was investigated if 3D-sound could be used to give the truck driver an audible and lifelike experience of the cyclists’ position, in relation...... to the truck, so the truck driver had an intuitive awareness of the cyclist’s position. It was concluded that the implementation of the 3D sound in the truck improved the situational awareness of the truck driver, and could therefore be deemed feasible for the application. Implementations of 3D sound...

  10. Computation of thermal properties via 3D homogenization of multiphase materials using FFT-based accelerated scheme

    Lemaitre, Sophie; Choi, Daniel; Karamian, Philippe

    2015-01-01

    In this paper we study the thermal effective behaviour for 3D multiphase composite material consisting of three isotropic phases which are the matrix, the inclusions and the coating media. For this purpose we use an accelerated FFT-based scheme initially proposed in Eyre and Milton (1999) to evaluate the thermal conductivity tensor. Matrix and spherical inclusions media are polymers with similar properties whereas the coating medium is metallic hence better conducting. Thus, the contrast between the coating and the others media is very large. For our study, we use RVEs (Representative volume elements) generated by RSA (Random Sequential Adsorption) method developed in our previous works, then, we compute effective thermal properties using an FFT-based homogenization technique validated by comparison with the direct finite elements method. We study the thermal behaviour of the 3D-multiphase composite material and we show what features should be taken into account to make the computational approach efficient.

  11. A 3D gravity and thermal model for the Barents Sea and Kara Sea

    Klitzke, Peter; Sippel, Judith; Faleide, Jan Inge; Scheck-Wenderoth, Magdalena

    2016-08-01

    In the frame of this study, we investigate the lithosphere-scale 3D physical state of the Barents Sea and Kara Sea region. Therefore, we test an existing 3D structural model against the gravitational field by considering the heterogeneous upper mantle to further assess the structural and density configuration of the continental crystalline crust. The resulting 3D density configuration of the crust is discussed in terms of its relationships with the spatial distribution of tectonically different domains. In addition, it provides the base for a lithology-controlled parameterisation of the crust with thermal properties to calculate the 3D conductive thermal field. The deeper thermal field is controlled by the depth configuration of the lithosphere-asthenosphere boundary. Accordingly, deeper isotherms such as the 450 °C isotherm deepen from below the rifted SW Barents Sea towards the intracratonic basins of the eastern Barents Sea and Kara Sea, indicating an increase of the lithospheric strength in the same direction. Temperature measurements of the upper 800 m below the SW Barents Sea reveal an increased thermal gradient which cannot be reproduced by a steady-state 3D conductive model alone. Beside fault-induced fluid flow to be active there, an alternative scenario could involve a phase of subsidence long enough to increase the temperature of the upper 800 m, followed by an uplift and erosion phase that prevented the positive thermal anomaly to propagate towards larger depths. The final lithosphere-scale 3D model is the first to integrate the geological, density and thermal configuration of the entire Barents Sea and Kara Sea region and hence provides an ideal base for future thermomechanical studies addressing, for instance, questions on the present-day, past and future relationships between lithospheric strength and deformation.

  12. General 3D Lumped Thermal Model with Various Boundary Conditions for High Power IGBT Modules

    Bahman, Amir Sajjad; Ma, Ke; Blaabjerg, Frede

    2016-01-01

    Accurate thermal dynamics modeling of high power Insulated Gate Bipolar Transistor (IGBT) modules is important information for the reliability analysis and thermal design of power electronic systems. However, the existing thermal models have their limits to correctly predict these complicated the...... the cooling system and power losses are modeled in the 3D thermal model, which can be adapted to different real field applications of power electronic converters. The accuracy of the proposed thermal model is verified by experimental results.......Accurate thermal dynamics modeling of high power Insulated Gate Bipolar Transistor (IGBT) modules is important information for the reliability analysis and thermal design of power electronic systems. However, the existing thermal models have their limits to correctly predict these complicated...

  13. In Situ Thermal Generation of Silver Nanoparticles in 3D Printed Polymeric Structures

    Erika Fantino

    2016-07-01

    Full Text Available Polymer nanocomposites have always attracted the interest of researchers and industry because of their potential combination of properties from both the nanofillers and the hosting matrix. Gathering nanomaterials and 3D printing could offer clear advantages and numerous new opportunities in several application fields. Embedding nanofillers in a polymeric matrix could improve the final material properties but usually the printing process gets more difficult. Considering this drawback, in this paper we propose a method to obtain polymer nanocomposites by in situ generation of nanoparticles after the printing process. 3D structures were fabricated through a Digital Light Processing (DLP system by disolving metal salts in the starting liquid formulation. The 3D fabrication is followed by a thermal treatment in order to induce in situ generation of metal nanoparticles (NPs in the polymer matrix. Comprehensive studies were systematically performed on the thermo-mechanical characteristics, morphology and electrical properties of the 3D printed nanocomposites.

  14. Regularity criteria for 3D Boussinesq equations with zero thermal diffusion

    Zhuan Ye

    2015-04-01

    Full Text Available In this article, we consider the three-dimensional (3D incompressible Boussinesq equations with zero thermal diffusion. We establish a regularity criterion for the local smooth solution in the framework of Besov spaces in terms of the velocity only.

  15. Estimation of the thermal conductivity of hemp based insulation material from 3D tomographic images

    El-Sawalhi, R.; Lux, J.; Salagnac, P.

    2016-08-01

    In this work, we are interested in the structural and thermal characterization of natural fiber insulation materials. The thermal performance of these materials depends on the arrangement of fibers, which is the consequence of the manufacturing process. In order to optimize these materials, thermal conductivity models can be used to correlate some relevant structural parameters with the effective thermal conductivity. However, only a few models are able to take into account the anisotropy of such material related to the fibers orientation, and these models still need realistic input data (fiber orientation distribution, porosity, etc.). The structural characteristics are here directly measured on a 3D tomographic image using advanced image analysis techniques. Critical structural parameters like porosity, pore and fiber size distribution as well as local fiber orientation distribution are measured. The results of the tested conductivity models are then compared with the conductivity tensor obtained by numerical simulation on the discretized 3D microstructure, as well as available experimental measurements. We show that 1D analytical models are generally not suitable for assessing the thermal conductivity of such anisotropic media. Yet, a few anisotropic models can still be of interest to relate some structural parameters, like the fiber orientation distribution, to the thermal properties. Finally, our results emphasize that numerical simulations on 3D realistic microstructure is a very interesting alternative to experimental measurements.

  16. Modeling and thermal investigations of the HTTR using the RELAP5-3D

    Scari, Maria E.; Nunes, Joao V. V.; Costa, Antonella L.; Pereira, Claubia; Mantecon, Javier G.; Veloso, Maria A. F., E-mail: melizabethscari@yahoo.com, E-mail: joaovitorn2@hotmail.com, E-mail: antonella@nuclear.ufmg.br, E-mail: claubia@nuclear.ufmg.br, E-mail: mantecon1987@gmail.com, E-mail: dora@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Escola de Engenharia. Departamento de Engenharia Nuclear

    2015-07-01

    A thermal model for the HTTR (High Temperature Engineering Test Reactor) has been developed using the RELAP5-3D code. The HTTR is a high temperature gas-cooled reactor (HTGR) developed, designed, constructed, and operated by the Japan Atomic Energy Research Institute (JAERI). It is a helium-cooled and graphite-moderated with a thermal power of 30 MW. In this work, a HTTR core inlet and outlet coolant temperatures, heat structures temperature and pressure drop have been reproduced using a RELAP5 model. The results have been compared with the available data. The calculations were performed using the point kinetic model. It is demonstrated that the developed model in the RELAP5-3D is capable of reproduce the thermal behavior of the reactor in steady state operation; however, more investigations are necessary to approach some parameters to those from the references. The next step is to complete the plant modeling and simulate transient conditions. (author)

  17. First vapor explosion calculations performed with MC3D thermal-hydraulic code

    Brayer, C.; Berthoud, G. [CEA Centre d`Etudes de Grenoble, 38 (France). Direction des Reacteurs Nucleaires

    1998-01-01

    This paper presents the first calculations performed with the `explosion` module of the multiphase computer code MC3D, which is devoted to the fine fragmentation and explosion phase of a fuel coolant interaction. A complete description of the physical laws included in this module is given. The fragmentation models, taking into account two fragmentation mechanisms, a thermal one and an hydrodynamic one, are also developed here. Results to some calculations to test the numerical behavior of MC3D and to test the explosion models in 1D or 2D are also presented. (author)

  18. 3D structure and conductive thermal field of the Upper Rhine Graben

    Freymark, Jessica; Sippel, Judith; Scheck-Wenderoth, Magdalena; Bär, Kristian; Stiller, Manfred; Fritsche, Johann-Gerhard; Kracht, Matthias

    2016-04-01

    The Upper Rhine Graben (URG) was formed as part of the European Cenozoic Rift System in a complex extensional setting. At present-day, it has a large socioeconomic relevance as it provides a great potential for geothermal energy production in Germany and France. For the utilisation of this energy resource it is crucial to understand the structure and the observed temperature anomalies in the rift basin. In the framework of the EU-funded "IMAGE" project (Integrated Methods for Advanced Geothermal Exploration), we apply a data-driven numerical modelling approach to quantify the processes and properties controlling the spatial distribution of subsurface temperatures. Typically, reservoir-scale numerical models are developed for predictions on the subsurface hydrothermal conditions and for reducing the risk of drilling non-productive geothermal wells. One major problem related to such models is setting appropriate boundary conditions that define, for instance, how much heat enters the reservoir from greater depths. Therefore, we first build a regional lithospheric-scale 3D structural model, which covers not only the entire URG but also adjacent geological features like the Black Forest and the Vosges Mountains. In particular, we use a multidisciplinary dataset (e.g. well data, seismic reflection data, existing structural models, gravity) to construct the geometries of the sediments, the crust and the lithospheric mantle that control the spatial distribution of thermal conductivity and radiogenic heat production and hence temperatures. By applying a data-based and lithology-dependent parameterisation of this lithospheric-scale 3D structural model and a 3D finite element method, we calculate the steady-state conductive thermal field for the entire region. Available measured temperatures (down to depths of up to 5 km) are considered to validate the 3D thermal model. We present major characteristics of the lithospheric-scale 3D structural model and results of the 3D

  19. 3D Nondestructive Visualization and Evaluation of TRISO Particles Distribution in HTGR Fuel Pebbles Using Cone-Beam Computed Tomography

    Gongyi Yu

    2017-01-01

    Full Text Available A nonuniform distribution of tristructural isotropic (TRISO particles within a high-temperature gas-cooled reactor (HTGR pebble may lead to excessive thermal gradients and nonuniform thermal expansion during operation. If the particles are closely clustered, local hotspots may form, leading to excessive stresses on particle layers and an increased probability of particle failure. Although X-ray digital radiography (DR is currently used to evaluate the TRISO distributions in pebbles, X-ray DR projection images are two-dimensional in nature, which would potentially miss some details for 3D evaluation. This paper proposes a method of 3D visualization and evaluation of the TRISO distribution in HTGR pebbles using cone-beam computed tomography (CBCT: first, a pebble is scanned on our high-resolution CBCT, and 2D cross-sectional images are reconstructed; secondly, all cross-sectional images are restructured to form the 3D model of the pebble; then, volume rendering is applied to segment and display the TRISO particles in 3D for visualization and distribution evaluation. For method validation, several pebbles were scanned and the 3D distributions of the TRISO particles within the pebbles were produced. Experiment results show that the proposed method provides more 3D than DR, which will facilitate pebble fabrication research and production quality control.

  20. Extreme low thermal conductivity in nanoscale 3D Si phononic crystal with spherical pores.

    Yang, Lina; Yang, Nuo; Li, Baowen

    2014-01-01

    In this work, we propose a nanoscale three-dimensional (3D) Si phononic crystal (PnC) with spherical pores, which can reduce the thermal conductivity of bulk Si by a factor up to 10,000 times at room temperature. Thermal conductivity of Si PnCs depends on the porosity, for example, the thermal conductivity of Si PnCs with porosity 50% is 300 times smaller than that of bulk Si. The phonon participation ratio spectra demonstrate that more phonons are localized as the porosity increases. The thermal conductivity is insensitive to the temperature changes from room temperature to 1100 K. The extreme-low thermal conductivity could lead to a larger value of ZT than unity as the periodic structure affects very little the electric conductivity.

  1. Multiscale 3D manufacturing: combining thermal extrusion printing with additive and subtractive direct laser writing

    Malinauskas, Mangirdas; Lukoševičius, Laurynas; MackevičiÅ«tÄ--, DovilÄ--; BalčiÅ«nas, Evaldas; RekštytÄ--, Sima; Paipulas, Domas

    2014-05-01

    A novel approach for efficient manufacturing of three-dimensional (3D) microstructured scaffolds designed for cell studies and tissue engineering applications is presented. A thermal extrusion (fused filament fabrication) 3D printer is employed as a simple and low-cost tabletop device enabling rapid materialization of CAD models out of biocompatible and biodegradable polylactic acid (PLA). Here it was used to produce cm- scale microporous (pore size varying from 100 to 400 µm) scaffolds. The fabricated objects were further laser processed in a direct laser writing (DLW) subtractive (ablation) and additive (lithography) manners. The first approach enables precise surface modification by creating micro-craters, holes and grooves thus increasing the surface roughness. An alternative way is to immerse the 3D PLA scaffold in a monomer solution and use the same DLW setup to refine its inner structure by fabricating dots, lines or a fine mesh on top as well as inside the pores of previously produced scaffolds. The DLW technique is empowered by ultrafast lasers - it allows 3D structuring with high spatial resolution in a great variety of photosensitive materials. Structure geometry on macro- to micro- scales could be finely tuned by combining these two fabrication techniques. Such artificial 3D substrates could be used for cell growth or as biocompatible-biodegradable implants. This combination of distinct material processing techniques enables rapid fabrication of diverse functional micro- featured and integrated devices. Hopefully, the proposed approach will find numerous applications in the field of ms, microfluidics, microoptics and many others.

  2. FISHEYE LENSES FOR 3D MODELING: EVALUATIONS AND CONSIDERATIONS

    L. Barazzetti

    2017-02-01

    Full Text Available Fisheye lenses are becoming more popular in complete image-based modelling projects of small and narrow spaces. The growing interest in fisheye lenses is confirmed by the availability of different commercial software incorporating a fisheye camera model. Such software are now able to carry out the steps of the image processing pipeline in a fully automated way, from camera calibration and orientation to dense matching, surface generation, and orthophoto production. This paper highlights the advantages (and disadvantages of fisheye lenses when used for 3D modelling projects through different commercial software. The goal is not only a comparison of commercial software, but also an analysis of the additional issues that arise when a fisheye lens is used for 3D modelling. Results confirm that a fisheye lens is suitable for accurate metric documentation, especially when limited space is available. On the other hand, additional issues where found during the camera calibration/image orientation step as well as the texture generation and orthophoto production phases, for which particular attention is required.

  3. Fisheye Lenses for 3d Modeling: Evaluations and Considerations

    Barazzetti, L.; Previtali, M.; Roncoroni, F.

    2017-02-01

    Fisheye lenses are becoming more popular in complete image-based modelling projects of small and narrow spaces. The growing interest in fisheye lenses is confirmed by the availability of different commercial software incorporating a fisheye camera model. Such software are now able to carry out the steps of the image processing pipeline in a fully automated way, from camera calibration and orientation to dense matching, surface generation, and orthophoto production. This paper highlights the advantages (and disadvantages) of fisheye lenses when used for 3D modelling projects through different commercial software. The goal is not only a comparison of commercial software, but also an analysis of the additional issues that arise when a fisheye lens is used for 3D modelling. Results confirm that a fisheye lens is suitable for accurate metric documentation, especially when limited space is available. On the other hand, additional issues where found during the camera calibration/image orientation step as well as the texture generation and orthophoto production phases, for which particular attention is required.

  4. Evaluating 3D-printed biomaterials as scaffolds for vascularized bone tissue engineering.

    Wang, Martha O; Vorwald, Charlotte E; Dreher, Maureen L; Mott, Eric J; Cheng, Ming-Huei; Cinar, Ali; Mehdizadeh, Hamidreza; Somo, Sami; Dean, David; Brey, Eric M; Fisher, John P

    2015-01-01

    There is an unmet need for a consistent set of tools for the evaluation of 3D-printed constructs. A toolbox developed to design, characterize, and evaluate 3D-printed poly(propylene fumarate) scaffolds is proposed for vascularized engineered tissues. This toolbox combines modular design and non-destructive fabricated design evaluation, evaluates biocompatibility and mechanical properties, and models angiogenesis.

  5. 3D thermal analysis of rectangular microscale inorganic light-emitting diodes in a pulsed operation

    Cui, Y.; Bian, Z.; Li, Y.; Xing, Y.; Song, J.

    2016-10-01

    Microscale inorganic light-emitting diodes (µ-ILEDs) have attracted much attention due to their excellent performance in biointegrated applications such as optogenetics. The thermal behaviors of µ-ILEDs are critically important since a certain temperature increase may degrade the LED performance and cause tissue lesion. The µ-ILEDs in a pulsed operation offer an advantage in thermal management. In this paper, a 3D analytic model, as validated by finite element analysis, is developed to study the thermal response of rectangular µ-ILEDs in a pulsed operation. A scaling law for the maximum normalized temperature increase of rectangular µ-ILEDs in terms of non-dimensional parameters is established. The influences of geometric (i.e. shape factor) and loading parameters (e.g. duty cycle and period) on the temperature increase are systematically investigated. These results are very helpful in designing µ-ILEDs by providing guidelines to avoid adverse thermal effects.

  6. Transient Thermal Analysis of 3-D Integrated Circuits Packages by the DGTD Method

    Li, Ping

    2017-03-11

    Since accurate thermal analysis plays a critical role in the thermal design and management of the 3-D system-level integration, in this paper, a discontinuous Galerkin time-domain (DGTD) algorithm is proposed to achieve this purpose. Such as the parabolic partial differential equation (PDE), the transient thermal equation cannot be directly solved by the DGTD method. To address this issue, the heat flux, as an auxiliary variable, is introduced to reduce the Laplace operator to a divergence operator. The resulting PDE is hyperbolic, which can be further written into a conservative form. By properly choosing the definition of the numerical flux used for the information exchange between neighboring elements, the hyperbolic thermal PDE can be solved by the DGTD together with the auxiliary differential equation. The proposed algorithm is a kind of element-level domain decomposition method, which is suitable to deal with multiscale geometries in 3-D integrated systems. To verify the accuracy and robustness of the developed DGTD algorithm, several representative examples are benchmarked.

  7. Reconstructing the Thermal Sunyaev-Zel'dovich Effect in 3D

    Pratten, Geraint

    2014-01-01

    The thermal Sunyaev-Zel'dovich (tSZ) effect is one of the most promising tools we have for probing the baryonic Universe. Unfortunately, the tSZ effect is defined as a line of sight projection of the thermal pressure fluctuations of free-electrons, compromising our ability to probe the thermal history of the Universe by smearing out the tSZ observables. This results in a loss of redshift information diminishing the power of tSZ observations. It is hoped that by cross-correlating the tSZ effect with external tracers we can recover a good fraction of the lost information. Weak lensing (WL) is thought to provide a relatively unbiased probe of the dark Universe in 3D with many upcoming WL surveys having sky coverage that overlaps with current tSZ surveys. Generalising the commonly used tomographic approach, we advocate the use of the spherical Fourier-Bessel (sFB) expansion as a means to perform a full analysis of cross-correlations between the projected (2D) tSZ Compton y-parameter maps and 3D WL-convergence kap...

  8. A 3D visible evaluation of landslide risk degree under integration of GIS and artificial intelligence

    QIAO; Jianping; ZHU; Axing; CHEN; Yongbo; WANG; Rongxun

    2003-01-01

    Artificial intelligence has been used to obtain background factors (basic environmental factors) from landslide specialists. A 3D visible evaluation map may be charted by fuzzy evaluation, and the traditional plane map may be decoded into a 3D map by using factor weight from specialists system and technology of RS and GIS for quantitative sampling of these factors.

  9. Evaluation of field development plans using 3-D reservoir modelling

    Seifert, D.; Lewis, J.J.M. [Heriot-Watt Univ., Edinburgh (United Kingdom); Newbery, J.D.H. [Conoco, UK Ltd., Aberdeen (United Kingdom)] [and others

    1997-08-01

    Three-dimensional reservoir modelling has become an accepted tool in reservoir description and is used for various purposes, such as reservoir performance prediction or integration and visualisation of data. In this case study, a small Northern North Sea turbiditic reservoir was to be developed with a line drive strategy utilising a series of horizontal producer and injector pairs, oriented north-south. This development plan was to be evaluated and the expected outcome of the wells was to be assessed and risked. Detailed analyses of core, well log and analogue data has led to the development of two geological {open_quotes}end member{close_quotes} scenarios. Both scenarios have been stochastically modelled using the Sequential Indicator Simulation method. The resulting equiprobable realisations have been subjected to detailed statistical well placement optimisation techniques. Based upon bivariate statistical evaluation of more than 1000 numerical well trajectories for each of the two scenarios, it was found that the wells inclinations and lengths had a great impact on the wells success, whereas the azimuth was found to have only a minor impact. After integration of the above results, the actual well paths were redesigned to meet external drilling constraints, resulting in substantial reductions in drilling time and costs.

  10. A 3D Finite Element evaluation of the exophthalmia reduction

    Luboz, V; Boutault, F; Swider, P; Payan, Y; Luboz, Vincent; Pedrono, Annaig; Boutault, Franck; Swider, Pascal; Payan, Yohan

    2003-01-01

    This paper presents a first evaluation of the feasibility of Finite Element modelling of the orbital decompression, in the context of exophthalmia. First simulations are carried out with data extracted from a patient TDM exam. Results seem to qualitatively validate the feasibility of the simulations, with a Finite Element analysis that converges and provides a backward movement of the ocular globe associated with displacements of the fat tissues through the sinuses. This FE model can help a surgeon for the planning of the exophthalmia reduction, and especially for the position and the size of the decompression hole. To get an estimation of the fat tissues volume affected by the surgery, an analytical model seems to provide quicker results for an equivalent efficiency.

  11. Understanding thermal Marangoni flow in water sessile evaporating drops via 3D-PTV

    Rossi, Massimiliano; Marin, Alvaro; Kaehler, Christian J.

    2016-11-01

    Understanding the flow inside sessile evaporating drops is of great interest both from a fundamental and technological point of view. Despite strong research efforts in the recent years, a complete picture on the phenomena involved in this process and a way to control them is still far to be reached. This is due to a lack of reliable experimental data on the internal flow but more dramatically on the interfacial flow. A relevant open debate concerns the role played by the Marangoni flow induced by thermal gradients. We recently show how 3D particle tracking techniques are suitable to measure the internal flow of drops and to derive quantities such as surface shear and surface tension differences. Such experiments also indicated an increase of the thermal Marangoni flow as the droplet becomes thinner, in disagreement with current theoretical models and simulations. A possible reason for that could be a discrepancy of the imposed boundary conditions in the simulations and the experimental ones. This work follows up these observations with fully 3D time-resolved measurements of the flow inside drops evaporating on a quartz substrate, which temperature is controlled using a feedback temperature control and a microscope incubator system. Supported by DFG, Grant No. KA 1808/22.

  12. Evaluation of stereoscopic 3D displays for image analysis tasks

    Peinsipp-Byma, E.; Rehfeld, N.; Eck, R.

    2009-02-01

    In many application domains the analysis of aerial or satellite images plays an important role. The use of stereoscopic display technologies can enhance the image analyst's ability to detect or to identify certain objects of interest, which results in a higher performance. Changing image acquisition from analog to digital techniques entailed the change of stereoscopic visualisation techniques. Recently different kinds of digital stereoscopic display techniques with affordable prices have appeared on the market. At Fraunhofer IITB usability tests were carried out to find out (1) with which kind of these commercially available stereoscopic display techniques image analysts achieve the best performance and (2) which of these techniques achieve a high acceptance. First, image analysts were interviewed to define typical image analysis tasks which were expected to be solved with a higher performance using stereoscopic display techniques. Next, observer experiments were carried out whereby image analysts had to solve defined tasks with different visualization techniques. Based on the experimental results (performance parameters and qualitative subjective evaluations of the used display techniques) two of the examined stereoscopic display technologies were found to be very good and appropriate.

  13. Modeling and simulation of 3D thermal stresses of large-sized castings in solidification processes

    2004-01-01

    When heavy machines and large scaled receiver system of communication equipment are manufactured, it always needs to produce large- sized steel castings, aluminum castings and etc. Some defects of hot cracking by thermal stress often appear during solidification process as these castings are produced, which results in failure of castings.Therefore predicting the effects of technological parameters for production of castings on the thermal stress during solidification process becomes an important means. In this paper, the mathematical models have been established and numerical calculation of temperature fields by using finite difference method (FDM) and then thermal stress fields by using finite element method (FEM) during solidification process of castings have been carried out. The technological parameters of production have been optimized by the results of calculation and the defects of hot cracking have been eliminated. Modeling and simulation of 3D thermal stress during solidification processes of large-sized castings provided a scientific basis, which promoted further development of advanced manufacturing technique.

  14. On the evaluation of 3D codecs on multiview autostereoscopic display

    Hanhart, Philippe; Ebrahimi, Touradj

    2013-01-01

    Evaluating the performance of different 3D codecs on multiview autostereoscopic monitor is a tedious process, as it requires the synthesis of a dense set of views. Therefore, it is legitimate to ask if evaluations could be performed on stereoscopic monitors instead and could lead to similar results as on multiview autostereoscopic monitors. This paper tries to answer to this question by analyzing a set of subjective scores resulting from evaluations of different 3D codecs on both display tech...

  15. 3D neutronic codes coupled with thermal-hydraulic system codes for PWR, and BWR and VVER reactors

    Langenbuch, S.; Velkov, K. [GRS, Garching (Germany); Lizorkin, M. [Kurchatov-Institute, Moscow (Russian Federation)] [and others

    1997-07-01

    This paper describes the objectives of code development for coupling 3D neutronics codes with thermal-hydraulic system codes. The present status of coupling ATHLET with three 3D neutronics codes for VVER- and LWR-reactors is presented. After describing the basic features of the 3D neutronic codes BIPR-8 from Kurchatov-Institute, DYN3D from Research Center Rossendorf and QUABOX/CUBBOX from GRS, first applications of coupled codes for different transient and accident scenarios are presented. The need of further investigations is discussed.

  16. The thermal regime of the Campi Flegrei magmatic system reconstructed through 3D numerical simulations

    Di Renzo, Valeria; Wohletz, Kenneth; Civetta, Lucia; Moretti, Roberto; Orsi, Giovanni; Gasparini, Paolo

    2016-12-01

    We illustrate a quantitative conductive/convective thermal model incorporating a wide range of geophysical, petrological, geological, geochemical and isotopical observations that constrain the thermal evolution and present state of the Campi Flegrei caldera (CFc) magmatic system. The proposed model has been computed on the basis of the current knowledge of: (1) the volcanic and magmatic history of the volcano over the last 44 ka, (2) its underlying crustal structure, and (3) the physical properties of the erupted magmas. 3D numerical simulations of heat conduction and convection within heterogeneous rock/magma materials with evolving heat sources and boundary conditions that simulate magma rise from a deep (≥ 8 km depth) to shallow (2-6 km) reservoirs, magma chamber formation, magma extrusion, caldera collapse, and intra-caldera hydrothermal convection, have been carried out. The evolution of the CFc magmatic system through time has been simulated through different steps related to its changes in terms of depth, location and size of magma reservoirs and their replenishment. The thermal modeling results show that both heat conduction and convection have played an important role in the CFc thermal evolution, although with different timing. The simulated present heat distribution is in agreement with the measured geothermal profiles (Agip, 1987), reproduces the thermal gradient peaks at the CFc margins in correspondence to the anomalies in surface gradients (Corrado et al., 1998), and suggests temperatures of 700 °C at depth of 4 km in the central portion of the caldera, in agreement with the estimated temperature for the brittle-ductile transition (Hill, 1992).

  17. Evaluation of isocenter reproducibility in telemedicine of 3D-radiotherapy treatment planning

    Hirota, Saeko; Tsujino, Kayoko; Kimura, Kouji; Takada, Yoshiki; Hishikawa, Yoshio; Kono, Michio [Hyogo Medical Center for Adults, Akashi (Japan); Soejima, Toshinori; Kodama, Akihisa

    2000-09-01

    To evaluate the utility in telemedicine of Three-Dimensional Radiotherapy Treatment Planning (tele-3D-RTP) and to examine the accuracy of isocenter reproducibility in its offline trial. CT data of phantoms and patients in the satellite hospital were transferred to our hospital via floppy-disk and 3D-radiotherapy plans were generated by 3D-RTP computer in our hospital. Profile data of CT and treatment beams in the satellite hospital were pre-installed into the computer. Tele-3D-RTPs were performed in 3 phantom plans and 14 clinical plans for 13 patients. Planned isocenters were well reproduced, especially in the immobilized head and neck/brain tumor cases, whose 3D-vector of aberration was 1.96{+-}1.38 (SD) mm. This teletherapy system is well applicable for practical use and can provides cost-reduction through sharing the resources of expensive equipment and radiation oncologists. (author)

  18. Engineering EMT using 3D micro-scaffold to promote hepatic functions for drug hepatotoxicity evaluation.

    Wang, Jingyu; Chen, Fengling; Liu, Longwei; Qi, Chunxiao; Wang, Bingjie; Yan, Xiaojun; Huang, Chenyu; Hou, Wei; Zhang, Michael Q; Chen, Yang; Du, Yanan

    2016-06-01

    Accompanied by decreased hepatic functions, epithelial-mesenchymal transition (EMT) was observed in two dimensional (2D) cultured hepatocytes with elongated morphology, loss of polarity and weakened cell-cell interaction, while upgrading to 3D culture has been considered as significant improvement of its 2D counterpart for hepatocyte maintenance. Here we hypothesize that 3D culture enhances hepatic functions through regulating the EMT status. Biomaterial-engineered EMT was achieved by culturing HepaRG as 3D spheroids (SP-3D) or 3D stretched cells (ST-3D) in non-adherent and adherent micro-scaffold respectively. In SP-3D, constrained EMT of HepaRG, a hepatic stem cell line, as represented by increased epithelial markers and decreased mesenchymal markers, was echoed by improved hepatic functions. To investigate the relationship between EMT status and hepatic functions, time-series RNA-Seq and gene network analysis were used for comparing different cell culture models, which identified histone deacetylases (HDACs) as key mediating factors. Protein analysis confirmed that high HDAC activity was correlated with high expression of Cadherin-1 (CDH1) and hepatic function genes, which were decreased upon HDAC inhibitor treatment in SP-3D, suggesting HDACs may play positive role in regulating EMT and hepatic functions. To illustrate the application of 3D micro-scaffold culture in drug safety evaluation, hepatotoxicity and metabolism assays of two hepatotoxins (i.e. N-acetyl-p-aminophenol and Doxorubicin) were performed and SP-3D showed more biomimetic toxicity response, indicating regulation of EMT as a vital consideration in designing 3D hepatocyte culture configuration.

  19. ON FUNDAMENTAL EVALUATION USING UAV IMAGERY AND 3D MODELING SOFTWARE

    K. Nakano

    2016-06-01

    Full Text Available Unmanned aerial vehicles (UAVs, which have been widely used in recent years, can acquire high-resolution images with resolutions in millimeters; such images cannot be acquired with manned aircrafts. Moreover, it has become possible to obtain a surface reconstruction of a realistic 3D model using high-overlap images and 3D modeling software such as Context capture, Pix4Dmapper, Photoscan based on computer vision technology such as structure from motion and multi-view stereo. 3D modeling software has many applications. However, most of them seem to not have obtained appropriate accuracy control in accordance with the knowledge of photogrammetry and/or computer vision. Therefore, we performed flight tests in a test field using an UAV equipped with a gimbal stabilizer and consumer grade digital camera. Our UAV is a hexacopter and can fly according to the waypoints for autonomous flight and can record flight logs. We acquired images from different altitudes such as 10 m, 20 m, and 30 m. We obtained 3D reconstruction results of orthoimages, point clouds, and textured TIN models for accuracy evaluation in some cases with different image scale conditions using 3D modeling software. Moreover, the accuracy aspect was evaluated for different units of input image—course unit and flight unit. This paper describes the fundamental accuracy evaluation for 3D modeling using UAV imagery and 3D modeling software from the viewpoint of close-range photogrammetry.

  20. On Fundamental Evaluation Using Uav Imagery and 3d Modeling Software

    Nakano, K.; Suzuki, H.; Tamino, T.; Chikatsu, H.

    2016-06-01

    Unmanned aerial vehicles (UAVs), which have been widely used in recent years, can acquire high-resolution images with resolutions in millimeters; such images cannot be acquired with manned aircrafts. Moreover, it has become possible to obtain a surface reconstruction of a realistic 3D model using high-overlap images and 3D modeling software such as Context capture, Pix4Dmapper, Photoscan based on computer vision technology such as structure from motion and multi-view stereo. 3D modeling software has many applications. However, most of them seem to not have obtained appropriate accuracy control in accordance with the knowledge of photogrammetry and/or computer vision. Therefore, we performed flight tests in a test field using an UAV equipped with a gimbal stabilizer and consumer grade digital camera. Our UAV is a hexacopter and can fly according to the waypoints for autonomous flight and can record flight logs. We acquired images from different altitudes such as 10 m, 20 m, and 30 m. We obtained 3D reconstruction results of orthoimages, point clouds, and textured TIN models for accuracy evaluation in some cases with different image scale conditions using 3D modeling software. Moreover, the accuracy aspect was evaluated for different units of input image—course unit and flight unit. This paper describes the fundamental accuracy evaluation for 3D modeling using UAV imagery and 3D modeling software from the viewpoint of close-range photogrammetry.

  1. 3D numerical model of the Omega Nebula (M17): simulated thermal X-ray emission

    Reyes-Iturbide, J; Rosado, M; Rodríguez-Gónzalez, A; González, R F; Esquivel, A

    2009-01-01

    We present 3D hydrodynamical simulations of the superbubble M17, also known as the Omega nebula, carried out with the adaptive grid code yguazu'-a, which includes radiative cooling. The superbubble is modelled considering the winds of 11 individual stars from the open cluster inside the nebula (NGC 6618), for which there are estimates of the mass loss rates and terminal velocities based on their spectral types. These stars are located inside a dense interstellar medium, and they are bounded by two dense molecular clouds. We carried out three numerical models of this scenario, considering different line of sight positions of the stars (the position in the plane of the sky is known, thus fixed). Synthetic thermal X-ray emission maps are calculated from the numerical models and compared with ROSAT observations of this astrophysical object. Our models reproduce successfully both the observed X-ray morphology and the total X-ray luminosity, without taking into account thermal conduction effects.

  2. Joint 3D modelling of the polarized Galactic synchrotron and thermal dust foreground diffuse emission

    Fauvet, L; Aumont, J; Désert, F X; Jaffe, T R; Banday, A J; Tristram, M; Waelkens, A H; Santos, D

    2010-01-01

    We present for the first time a coherent model of the polarized Galactic synchrotron and thermal dust emissions which are the main diffuse foreground for the measurement of the polarized power spectra of the CMB fluctuations with the Planck satellite mission. We produce 3D models of the Galactic magnetic field including regular and turbulent components, and of the distribution of matter in the Galaxy, relativistic electrons and dust grains. By integrating along the line of sight we construct maps of the polarized Galactic synchrotron and thermal dust emission for each of these models and compare them to currently available data. We consider the 408 MHz all-sky continuum survey, the 23 GHz band of the Wilkinson Microwave Anisotropy Probe and the 353 GHz Archeops data.}{The best-fit parameters obtained are consistent with previous estimates in the literature based only on synchrotron emission and pulsar rotation measurements. They allows us to reproduce the large scale structures observed on the data. Poorly un...

  3. Comprehensive evaluation of latest 2D/3D monitors and comparison to a custom-built 3D mirror-based display in laparoscopic surgery

    Wilhelm, Dirk; Reiser, Silvano; Kohn, Nils; Witte, Michael; Leiner, Ulrich; Mühlbach, Lothar; Ruschin, Detlef; Reiner, Wolfgang; Feussner, Hubertus

    2014-03-01

    Though theoretically superior, 3D video systems did not yet achieve a breakthrough in laparoscopic surgery. Furthermore, visual alterations, such as eye strain, diplopia and blur have been associated with the use of stereoscopic systems. Advancements in display and endoscope technology motivated a re-evaluation of such findings. A randomized study on 48 test subjects was conducted to investigate whether surgeons can benefit from using most current 3D visualization systems. Three different 3D systems, a glasses-based 3D monitor, an autostereoscopic display and a mirror-based theoretically ideal 3D display were compared to a state-of-the-art 2D HD system. The test subjects split into a novice and an expert surgeon group, which high experience in laparoscopic procedures. Each of them had to conduct a well comparable laparoscopic suturing task. Multiple performance parameters like task completion time and the precision of stitching were measured and compared. Electromagnetic tracking provided information on the instruments path length, movement velocity and economy. The NASA task load index was used to assess the mental work load. Subjective ratings were added to assess usability, comfort and image quality of each display. Almost all performance parameters were superior for the 3D glasses-based display as compared to the 2D and the autostereoscopic one, but were often significantly exceeded by the mirror-based 3D display. Subjects performed the task at average 20% faster and with a higher precision. Work-load parameters did not show significant differences. Experienced and non-experienced laparoscopists profited equally from 3D. The 3D mirror system gave clear evidence for additional potential of 3D visualization systems with higher resolution and motion parallax presentation.

  4. Network level pavement evaluation with 1 mm 3D survey system

    Kelvin C.P. Wang

    2015-12-01

    Full Text Available The latest iteration of PaveVision3D Ultra can obtain true 1 mm resolution 3D data at full-lane coverage in all 3 directions at highway speed up to 60 mph. This paper introduces the PaveVision3D Ultra technology for rapid network level pavement survey on approximately 1280 center miles of Oklahoma interstate highways. With sophisticated automated distress analyzer (ADA software interface, the collected 1 mm 3D data provide Oklahoma Department of Transportation (ODOT with comprehensive solutions for automated evaluation of pavement surface including longitudinal profile for roughness, transverse profile for rutting, predicted hydroplaning speed for safety analysis, and cracking and various surface defects for distresses. The pruned exact linear time (PELT method, an optimal partitioning algorithm, is implemented to identify change points and dynamically determine homogeneous segments so as to assist ODOT effectively using the available 1 mm 3D pavement surface condition data for decision-making. The application of 1 mm 3D laser imaging technology for network survey is unprecedented. This innovative technology allows highway agencies to access its options in using the 1 mm 3D system for its design and management purposes, particularly to meet the data needs for pavement management system (PMS, pavement ME design and highway performance monitoring system (HPMS.

  5. A Fast Hybrid (3-D/1-D) Model for Thermal Radiative Transfer in Cirrus via Successive Orders of Scattering

    Fauchez, Thomas; Davis, Anthony B.; Cornet, Celine; Szczap, Frederic; Platnick, Steven; Dubuisson, Philippe; Thieuleux, Francois

    2017-01-01

    We investigate the impact of cirrus cloud heterogeneity on the direct emission by cloud or surface and on the scattering by ice particles in the thermal infrared (TIR). Realistic 3-D cirri are modeled with the 3DCLOUD code, and top-of-atmosphere radiances are simulated by the 3-D Monte Carlo radiative transfer (RT) algorithm 3DMCPOL for two (8.65 micrometers and 12.05 micrometers) channels of the Imaging Infrared Radiometer on CALIPSO. At nadir, comparisons of 1-D and 3-D RT show that 3-D radiances are larger than their 1-D counterparts for direct emission but smaller for scattered radiation. For our cirrus cases, 99% of the 3-D total radiance is computed by the third scattering order, which corresponds to 90% of the total computational effort, but larger optical thicknesses need more scattering orders. To radically accelerate the 3-D RT computations (using only few percent of 3-D RT time with a Monte Carlo code), even in the presence of large optical depths, we develop a hybrid model based on exact 3-D direct emission, the first scattering order from 1-D in each homogenized column, and an empirical adjustment linearly dependent on the optical thickness to account for higher scattering orders. Good agreement is found between the hybrid model and the exact 3-D radiances for two very different cirrus models without changing the empirical parameters. We anticipate that a future deterministic implementation of the hybrid model will be fast enough to process multiangle thermal imagery in a practical tomographic reconstruction of 3-D cirrus fields.

  6. Evaluation of Model Recognition for Grammar-Based Automatic 3d Building Model Reconstruction

    Yu, Qian; Helmholz, Petra; Belton, David

    2016-06-01

    In recent years, 3D city models are in high demand by many public and private organisations, and the steadily growing capacity in both quality and quantity are increasing demand. The quality evaluation of these 3D models is a relevant issue both from the scientific and practical points of view. In this paper, we present a method for the quality evaluation of 3D building models which are reconstructed automatically from terrestrial laser scanning (TLS) data based on an attributed building grammar. The entire evaluation process has been performed in all the three dimensions in terms of completeness and correctness of the reconstruction. Six quality measures are introduced to apply on four datasets of reconstructed building models in order to describe the quality of the automatic reconstruction, and also are assessed on their validity from the evaluation point of view.

  7. Evaluation of 3D printed materials used to print WR10 horn antennas

    Köhler, Elof; Rahiminejad, Sofia; Enoksson, Peter

    2016-10-01

    A WR10 waveguide horn antenna is 3D printed with three different materials. The antennas are printed on a fusion deposition modeling delta 3D printer built in house at Chalmers University of Technology. The different plastic materials used are an electrically conductive Acrylonitrile butadiene styrene (ABS), a thermally conductive polylactic acid containing 35% copper, and a tough Amphora polymer containing at least 20% carbon fiber. The antennas are all printed with a 0.25 mm nozzle and 100 μm layer thickness and the software settings are tuned to give maximum quality for each material. The three 3D printed horn antennas are compared when it comes to cost, time and material properties.

  8. Mobile 3D quality of experience evaluation: a hybrid data collection and analysis approach

    Utriainen, Timo; Häyrynen, Jyrki; Jumisko-Pyykkö, Satu; Boev, Atanas; Gotchev, Atanas; Hannuksela, Miska M.

    2011-02-01

    The paper presents a hybrid approach to study the user's experienced quality of 3D visual content on mobile autostereoscopic displays. It combines extensive subjective tests with collection and objective analysis of eye-tracked data. 3D cues which are significant for mobiles are simulated in the generated 3D test content. The methodology for conducting subjective quality evaluation includes hybrid data-collection of quantitative quality preferences, qualitative impressions, and binocular eye-tracking. We present early results of the subjective tests along with eye movement reaction times, areas of interest and heatmaps obtained from raw eye-tracked data after statistical analysis. The study contributes to the question what is important to be visualized on portable auto-stereoscopic displays and how to maintain and visually enhance the quality of 3D content for such displays.

  9. 3D thermal analysis of a permanent magnet motor with cooling fans

    Zheng TAN; Xue-guan SONG; Bing JI; Zheng LIU; Ji-en MA; Wen-ping CAO

    2015-01-01

    Overheating of permanent magnet (PM) machines has become a major technical challenge as it gives rise to magnet demagnetization, degradation of insulation materials, and loss of motor efficiency. This paper proposes a state-of-the-art cooling system for an axial flux permanent magnet (AFPM) machine with the focus on its structural optimization. A computational fluid dynamics (CFD) simulation with thermal consideration has been shown to be an efficient approach in the literature and is thus employed in this work. Meanwhile, a simplified numerical approach to the AFPM machine with complex configuration in 3D consisting of conduction, forced convection, and conjugate heat transfer is taken as a case study. Different simplification meth-ods (including configuration and working conditions) and two optimized fans for forced convection cooling are designed and installed on the AFPM machine and compared to a natural convection cooling system. The results show that the proposed ap-proach is effective for analyzing the thermal performance of a complex AFPM machine and strikes a balance between reasona-ble simplification, accuracy, and computational resource.%目的:提出一种适合永磁电机的冷却系统设计方案,降低电机本体温度。  创新点:提出一种适合永磁电机热分析的CFD仿真模型。  方法:采用计算流体动力学方法对包含冷却风扇的永磁电机进行空间三维热力学分析和优化设计。  结论:本文提出并优化后的冷却风扇可有效降低永磁电机的最高和平均温度。

  10. A novel 3D sandwich structure of hybrid graphite nanosheets and silver nanowires as fillers for improved thermal conductivity

    Zhuang, Xiao; Zhou, Yongcun; Liu, Feng

    2017-01-01

    We explored a novel 3D sandwich structure of fillers in the polymer matrix to enhance thermal conductivity. A variety of fillers in the polymer matrix play a significant role in the physical properties of the composite. Fillers containing particle and line structures are popular, and enhance the thermal and electrical conductivities. Therefore, filler-based matrix network improves conductivity. We propose a sandwich structure consisting of hybrid graphite nanosheets (two dimensions), and silver nanowires (AgNWs) (one dimension), to create a 3D sandwich structure of polyimide matrix with improved thermal conductivity. Surface treatment of graphite and silver nanowires were conducted to reduce the dielectric constant of the composite. We designed the filler of 20 wt% resulting in a high thermal conductivity of 3.21 W m‑1 K‑1 with 15% C@SiO2 and 5% AgNWs@SiO2 filler loading. The novel combination and structure markedly enhanced the thermal conductivity of the composite.

  11. Micro-Structured Two-Component 3D Metamaterials with Negative Thermal-Expansion Coefficient from Positive Constituents

    Qu, Jingyuan; Kadic, Muamer; Naber, Andreas; Wegener, Martin

    2017-01-01

    Controlling the thermal expansion of materials is of great technological importance. Uncontrolled thermal expansion can lead to failure or irreversible destruction of structures and devices. In ordinary crystals, thermal expansion is governed by the asymmetry of the microscopic binding potential, which cannot be adjusted easily. In artificial crystals called metamaterials, thermal expansion can be controlled by structure. Here, following previous theoretical work, we fabricate three-dimensional (3D) two-component polymer micro-lattices by using gray-tone laser lithography. We perform cross-correlation analysis of optical microscopy images taken at different sample temperatures. The derived displacement-vector field reveals that the thermal expansion and resulting bending of the bi-material beams leads to a rotation of the 3D chiral crosses arranged onto a 3D checkerboard pattern within one metamaterial unit cell. These rotations can compensate the expansion of the all positive constituents, leading to an effectively near-zero thermal length-expansion coefficient, or over-compensate the expansion, leading to an effectively negative thermal length-expansion coefficient. This evidences a striking level of thermal-expansion control.

  12. Interface requirements to couple thermal-hydraulic codes to 3D neutronic codes

    Langenbuch, S.; Austregesilo, H.; Velkov, K. [GRS, Garching (Germany)] [and others

    1997-07-01

    The present situation of thermalhydraulics codes and 3D neutronics codes is briefly described and general considerations for coupling of these codes are discussed. Two different basic approaches of coupling are identified and their relative advantages and disadvantages are discussed. The implementation of the coupling for 3D neutronics codes in the system ATHLET is presented. Meanwhile, this interface is used for coupling three different 3D neutronics codes.

  13. 3D thermal history and maturity modelling of the Levant Basin and Margin

    Daher, Samer Bou; Ducros, Mathieu; Michel, Pauline; Nader, Fadi H.; Littke, Ralf

    2015-04-01

    The gas discoveries recorded in the Levant Basin in the last decade have redirected the industrial and academic communities' interest to this frontier basin and its surroundings. The reported gas in Miocene reservoirs has been assumed to be derived from biogenic sources, although little data has been published so far. The thickness of the sedimentary column and the presence of direct hydrocarbon indicators (DHI) observed in the seismic data suggest the presence of promising prospective thermogenic petroleum systems in deeper intervals in the Levant Basin and along its Margin. In this study we present a large scale 3D thermal history and maturity model of the Levant Basin and Margin, integrating all available calibration data, source rock information collected from onshore Lebanon, and published data. In the first part we will present the main input and assumptions that were made in terms of thicknesses, lithologies, and boundary conditions. In the second part we will discuss the analysed source rocks, their petroleum generation potential and their kinetics. In the third part we will present modelling results including depth maps for key isotherms in addition to transformation ratio and vitrinite reflectance maps for proven and speculative source rocks at different time steps. This will provide a comprehensive assessment of the potential thermogenic petroleum systems in the study area, and allow us to illustrate and discuss the differences between the basinal, marginal, and onshore part of the study area as well as the potential of the northern vis a vis the southern offshore Levant Basin. This model will also allow us to analyse the sensitivity of the system to the various poorly constrained parameters in frontier basins (e.g. crustal thickness, rifting phases, lithologies) and thus identify the most critical data to be collected for future exploration and de-risking strategies.

  14. A novel 3D-layered electrochemical-thermal coupled model strategy for the nail-penetration process simulation

    Liang, Guozhou; Zhang, Yiming; Han, Qi; Liu, Zhaoping; Jiang, Zhen; Tian, Shuang

    2017-02-01

    The safety is one of the persisting concerns related with Lithium-ion (Li-ion) batteries, among which the internal short-circuit is the most dangerous abusive situation and has always been the root cause for several catastrophic accidents in recent years. In this work, a 3D-layered electrochemical-thermal coupled model is employed to investigate the nail-penetration process in a Li-ion cell. The model is based on multilayer construction of a cell, and an effective strategy to evaluate the short-circuit area equivalent resistance (i.e. the equivalent resistance of short-circuit area that is caused by nail-penetration) during the penetration process is proposed. The developed model is proved to have capability of estimating the thermal runaway time, as well as the temperature distribution during nail-penetration process. It is also found that the active material loss during the nail-penetration process can be reconstructed by utilizing the developed model, which could provide understandings about the side reactions inside the cell during the nail-penetration process. The present study provides some insights about the nail-penetration process, and can be treated as a useful tool that helps the design of Li-ion cells for improving safety.

  15. Evaluation of low-dose limits in 3D-2D rigid registration for surgical guidance

    Uneri, A.; Wang, A. S.; Otake, Y.; Kleinszig, G.; Vogt, S.; Khanna, A. J.; Gallia, G. L.; Gokaslan, Z. L.; Siewerdsen, J. H.

    2014-09-01

    An algorithm for intensity-based 3D-2D registration of CT and C-arm fluoroscopy is evaluated for use in surgical guidance, specifically considering the low-dose limits of the fluoroscopic x-ray projections. The registration method is based on a framework using the covariance matrix adaptation evolution strategy (CMA-ES) to identify the 3D patient pose that maximizes the gradient information similarity metric. Registration performance was evaluated in an anthropomorphic head phantom emulating intracranial neurosurgery, using target registration error (TRE) to characterize accuracy and robustness in terms of 95% confidence upper bound in comparison to that of an infrared surgical tracking system. Three clinical scenarios were considered: (1) single-view image + guidance, wherein a single x-ray projection is used for visualization and 3D-2D guidance; (2) dual-view image + guidance, wherein one projection is acquired for visualization, combined with a second (lower-dose) projection acquired at a different C-arm angle for 3D-2D guidance; and (3) dual-view guidance, wherein both projections are acquired at low dose for the purpose of 3D-2D guidance alone (not visualization). In each case, registration accuracy was evaluated as a function of the entrance surface dose associated with the projection view(s). Results indicate that images acquired at a dose as low as 4 μGy (approximately one-tenth the dose of a typical fluoroscopic frame) were sufficient to provide TRE comparable or superior to that of conventional surgical tracking, allowing 3D-2D guidance at a level of dose that is at most 10% greater than conventional fluoroscopy (scenario #2) and potentially reducing the dose to approximately 20% of the level in a conventional fluoroscopically guided procedure (scenario #3).

  16. An Exploratory Evaluation of User Interfaces for 3D Audio Mixing

    Gelineck, Steven; Korsgaard, Dannie Michael

    2015-01-01

    The paper presents an exploratory evaluation comparing different versions of a mid-air gesture based interface for mixing 3D audio exploring: (1) how such an interface generally compares to a more traditional physical interface, (2) methods for grabbing/releasing audio channels in mid-air and (3)...

  17. Ground truth evaluation of computer vision based 3D reconstruction of synthesized and real plant images

    Nielsen, Michael; Andersen, Hans Jørgen; Slaughter, David

    2007-01-01

    There is an increasing interest in using 3D computer vision in precision agriculture. This calls for better quantitative evaluation and understanding of computer vision methods. This paper proposes a test framework using ray traced crop scenes that allows in-depth analysis of algorithm performance...

  18. Performance evaluation of 3D-DDTC detectors on p-type substrates

    Dalla Betta, Gian-Franco, E-mail: dallabe@disi.unitn.i [Dipartimento Ingegneria e Scienza dell' Informazione, Universita di Trento, and INFN Trento, via Sommarive 14, 38123 Povo di Trento (Italy); Boscardin, Maurizio [Fondazione Bruno Kessler (FBK-irst), via Sommarive 18, 38123 Povo di Trento (Italy); Bosisio, Luciano [Dipartimento di Fisica, Universita di Trieste, and INFN Trieste, via A. Valerio 2, 34127 Trieste (Italy); Koehler, Michael; Parzefall, Ulrich [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Ronchin, Sabina [Fondazione Bruno Kessler (FBK-irst), via Sommarive 18, 38123 Povo di Trento (Italy); Wiik, Liv [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Zoboli, Andrea [Dipartimento Ingegneria e Scienza dell' Informazione, Universita di Trento, and INFN Trento, via Sommarive 14, 38123 Povo di Trento (Italy); Zorzi, Nicola [Fondazione Bruno Kessler (FBK-irst), via Sommarive 18, 38123 Povo di Trento (Italy)

    2010-12-11

    In this work, we report on the noise and signal properties of n-on-p, 3D Double-Side Double Type Column (3D-DDTC) detectors fabricated at FBK-irst (Trento, Italy). Compared to full 3D detectors, devices made with this approach allow for a simpler fabrication process, but the efficiency and speed of the charge collection process critically depend on the column overlap and should be carefully evaluated. Measurements were performed on detectors in the microstrip configuration coupled to the ATLAS ABCD3T binary read-out. Spatially resolved signal efficiency tests made with a pulsed infrared laser setup and charge collection efficiency tests made with a {beta} source setup are here reported.

  19. 3D evaluation of palatal rugae for human identification using digital study models

    Taneva, Emilia D.; Johnson, Andrew; Viana, Grace; Evans, Carla A.

    2015-01-01

    Background: While there is literature suggesting that the palatal rugae could be used for human identification, most of these studies use two-dimensional (2D) approach. Aim: The aims of this study were to evaluate palatal ruga patterns using three-dimensional (3D) digital models; compare the most clinically relevant digital model conversion techniques for identification of the palatal rugae; develop a protocol for overlay registration; determine changes in palatal ruga individual patterns through time; and investigate the efficiency and accuracy of 3D matching processes between different individuals’ patterns. Material and Methods: Five cross sections in the anteroposterior dimension and four cross sections in the transverse dimension were computed which generated 18 2D variables. In addition, 13 3D variables were defined: The posterior point of incisive papilla (IP), and the most medial and lateral end points of the palatal rugae (R1MR, R1ML, R1LR, R1LL, R2MR, R2ML, R2LR, R2LL, R3MR, R3ML, R3LR, and R3LL). The deviation magnitude for each variable was statistically analyzed in this study. Five different data sets with the same 31 landmarks were evaluated in this study. Results: The results demonstrated that 2D images and linear measurements in the anteroposterior and transverse dimensions were not sufficient for comparing different digital model conversion techniques using the palatal rugae. 3D digital models proved to be a highly effective tool in evaluating different palatal ruga patterns. The 3D landmarks showed no statistically significant mean differences over time or as a result of orthodontic treatment. No statistically significant mean differences were found between different digital model conversion techniques, that is, between OrthoCAD™ and Ortho Insight 3D™, and between Ortho Insight 3D™ and the iTero® scans, when using 12 3D palatal rugae landmarks for comparison. Conclusion: Although 12 palatal 3D landmarks could be used for human

  20. 3D evaluation of palatal rugae for human identification using digital study models

    Emilia D Taneva

    2015-01-01

    Full Text Available Background: While there is literature suggesting that the palatal rugae could be used for human identification, most of these studies use two-dimensional (2D approach. Aim: The aims of this study were to evaluate palatal ruga patterns using three-dimensional (3D digital models; compare the most clinically relevant digital model conversion techniques for identification of the palatal rugae; develop a protocol for overlay registration; determine changes in palatal ruga individual patterns through time; and investigate the efficiency and accuracy of 3D matching processes between different individuals′ patterns. Material and Methods: Five cross sections in the anteroposterior dimension and four cross sections in the transverse dimension were computed which generated 18 2D variables. In addition, 13 3D variables were defined: The posterior point of incisive papilla (IP, and the most medial and lateral end points of the palatal rugae (R1MR, R1ML, R1LR, R1LL, R2MR, R2ML, R2LR, R2LL, R3MR, R3ML, R3LR, and R3LL. The deviation magnitude for each variable was statistically analyzed in this study. Five different data sets with the same 31 landmarks were evaluated in this study. Results: The results demonstrated that 2D images and linear measurements in the anteroposterior and transverse dimensions were not sufficient for comparing different digital model conversion techniques using the palatal rugae. 3D digital models proved to be a highly effective tool in evaluating different palatal ruga patterns. The 3D landmarks showed no statistically significant mean differences over time or as a result of orthodontic treatment. No statistically significant mean differences were found between different digital model conversion techniques, that is, between OrthoCAD™ and Ortho Insight 3D™, and between Ortho Insight 3D™ and the iTero; scans, when using 12 3D palatal rugae landmarks for comparison. Conclusion: Although 12 palatal 3D landmarks could be used for

  1. Double casting prototyping with a thermal aging step for fabrication of 3D microstructures in poly(dimethylsiloxane

    Karina Kwapiszewska

    2016-11-01

    Full Text Available The paper describes a cheap and accessible technique of a poly(dimethylsiloxane (PDMS master treatment by thermal aging as a step of double casting microfabrication process. Three-dimensional PDMS microstructures could have been achieved using this technique. It was proved, that thermal aging changes nanotopology of a PDMS surface and thus enhances efficiency of double casting prototyping. The thermally aged PDMS master could have been used for multiple and correct replication of over 98% of the fabricated microstructures. Moreover, lack of chemical modification preserved the biocompatibility of PDMS devices. The fabricated microstructures were successfully utilized for 3D cell culture.

  2. X-ray diffraction study on the thermal properties of CuMPt6 (M= 3d elements) alloys

    2009-01-01

    The effect of ternary addition of the 3d elements Ti, V, Cr, Mn, Fe, Co and Ni to CuPt3 to form ternary CuMPt6 alloys on the thermal properties was investigated using high-temperature X-ray diffraction method. Data obtained were utilized to determine the lattice parameters, coefficients of thermal expansion, Debye temperature and mean-square displacements of an atom. It was found that the addition increases the lattice spacing, increases the degree of thermal expansion and lowers the Debye te...

  3. Ice-Templated Assembly Strategy to Construct 3D Boron Nitride Nanosheet Networks in Polymer Composites for Thermal Conductivity Improvement.

    Zeng, Xiaoliang; Yao, Yimin; Gong, Zhengyu; Wang, Fangfang; Sun, Rong; Xu, Jianbin; Wong, Ching-Ping

    2015-12-01

    Owing to the growing heat removal issue of modern electronic devices, polymer composites with high thermal conductivity have drawn much attention in the past few years. However, a traditional method to enhance the thermal conductivity of the polymers by addition of inorganic fillers usually creates composite with not only limited thermal conductivity but also other detrimental effects due to large amount of fillers required. Here, novel polymer composites are reported by first constructing 3D boron nitride nanosheets (3D-BNNS) network using ice-templated approach and then infiltrating them with epoxy matrix. The obtained polymer composites exhibit a high thermal conductivity (2.85 W m(-1) K(-1)), a low thermal expansion coefficient (24-32 ppm K(-1)), and an increased glass transition temperature (T(g)) at relatively low BNNSs loading (9.29 vol%). These results demonstrate that this approach opens a new avenue for design and preparation of polymer composites with high thermal conductivity. The polymer composites are potentially useful in advanced electronic packaging techniques, namely, thermal interface materials, underfill materials, molding compounds, and organic substrates.

  4. Investigation of seasonal thermal flow in a real dam reservoir using 3-D numerical modeling

    Üneş Fatih

    2015-03-01

    Full Text Available Investigations indicate that correct estimation of seasonal thermal stratification in a dam reservoir is very important for the dam reservoir water quality modeling and water management problems. The main aim of this study is to develop a hydrodynamics model of an actual dam reservoir in three dimensions for simulating a real dam reservoir flows for different seasons. The model is developed using nonlinear and unsteady continuity, momentum, energy and k-ε turbulence model equations. In order to include the Coriolis force effect on the flow in a dam reservoir, Coriolis force parameter is also added the model equations. Those equations are constructed using actual dimensions, shape, boundary and initial conditions of the dam and reservoir. Temperature profiles and flow visualizations are used to evaluate flow conditions in the reservoir. Reservoir flow’s process and parameters are determined all over the reservoir. The mathematical model developed is capable of simulating the flow and thermal characteristics of the reservoir system for seasonal heat exchanges. Model simulations results obtained are compared with field measurements obtained from gauging stations for flows in different seasons. The results show a good agreement with the field measurements.

  5. Uncertainty propagation in a 3-D thermal code for performance assessment of a nuclear waste disposal

    Dutfoy, A. [Electricite de France (EDF), Research and Development Div., Safety and Reliability Branch, ESF, 92 - Clamart (France); Ritz, J.B. [Electricite de France (EDF), Research and Development Div., Fluid Mechanics and Heat Transfer, MFTT, 78 - Chatou (France)

    2001-07-01

    Given the very large time scale involved, the performance assessment of a nuclear waste repository requires numerical modelling. Because we are uncertain of the exact value of the input parameters, we have to analyse the impact of these uncertainties on the outcome of the physical models. The EDF Division Research and Development has set a reliability method to propagate these uncertainties or variability through models which requires much less physical simulations than the usual simulation methods. We apply the reliability method MEFISTO to a base case modelling the heat transfers in a virtual disposal in the future site of the French underground research laboratory, in the East of France. This study is led in collaboration with ANDRA which is the French Nuclear Waste Management Agency. With this exercise, we want to evaluate the thermal behaviour of a concept related to the variation of physical parameters and their uncertainty. (author)

  6. 3D-FEM electrical-thermal-mechanical analysis and experiment of Si-based MEMS infrared emitters

    Wang, Xiang; Wang, Na; Chen, Ran-Bin; San, Hai-Sheng; Chen, Xu-Yuan

    2016-11-01

    Designs, simulations, and fabrications of silicon-based MEMS infrared (IR) emitters for gas sensing application are presented. A 3D finite element method (3D-FEM) was used to analyze the coupled electrical-thermal-mechanical properties of a bridge hotplate structure (BHS) IR emitter and closed hotplate structure (CHS) IR emitter using Joule heating and thermal expansion models of COMSOL™. The IR absorptions of n- and p-silicon were calculated for the design of self-heating structure. The BHS and CHS IR emitters were fabricated synchronously using micro-electromechanical systems technology for a direct performance comparison. Both types of IR emitters were characterized by electrical and optical measurements. The experimental results show that BHS IR emitters have higher radiation density, lower power consumption, and faster frequency-response than CHS IR emitters due to the use of a thermal isolation structure and self-heating structure. Meanwhile, the simulated results agree well with the corresponding measured results, which indicate that the 3D-FEM-model is effective and can be used in the optimal design of electro-thermal devices.

  7. A method for the evaluation of thousands of automated 3D stem cell segmentations.

    Bajcsy, P; Simon, M; Florczyk, S J; Simon, C G; Juba, D; Brady, M C

    2015-12-01

    There is no segmentation method that performs perfectly with any dataset in comparison to human segmentation. Evaluation procedures for segmentation algorithms become critical for their selection. The problems associated with segmentation performance evaluations and visual verification of segmentation results are exaggerated when dealing with thousands of three-dimensional (3D) image volumes because of the amount of computation and manual inputs needed. We address the problem of evaluating 3D segmentation performance when segmentation is applied to thousands of confocal microscopy images (z-stacks). Our approach is to incorporate experimental imaging and geometrical criteria, and map them into computationally efficient segmentation algorithms that can be applied to a very large number of z-stacks. This is an alternative approach to considering existing segmentation methods and evaluating most state-of-the-art algorithms. We designed a methodology for 3D segmentation performance characterization that consists of design, evaluation and verification steps. The characterization integrates manual inputs from projected surrogate 'ground truth' of statistically representative samples and from visual inspection into the evaluation. The novelty of the methodology lies in (1) designing candidate segmentation algorithms by mapping imaging and geometrical criteria into algorithmic steps, and constructing plausible segmentation algorithms with respect to the order of algorithmic steps and their parameters, (2) evaluating segmentation accuracy using samples drawn from probability distribution estimates of candidate segmentations and (3) minimizing human labour needed to create surrogate 'truth' by approximating z-stack segmentations with 2D contours from three orthogonal z-stack projections and by developing visual verification tools. We demonstrate the methodology by applying it to a dataset of 1253 mesenchymal stem cells. The cells reside on 10 different types of biomaterial

  8. Evaluating 3D registration of CT-scan images using crest lines

    Ayache, Nicholas; Gueziec, Andre P.; Thirion, Jean-Philippe; Gourdon, A.; Knoplioch, Jerome

    1993-06-01

    We consider the issue of matching 3D objects extracted from medical images. We show that crest lines computed on the object surfaces correspond to meaningful anatomical features, and that they are stable with respect to rigid transformations. We present the current chain of algorithmic modules which automatically extract the major crest lines in 3D CT-Scan images, and then use differential invariants on these lines to register together the 3D images with a high precision. The extraction of the crest lines is done by computing up to third order derivatives of the image intensity function with appropriate 3D filtering of the volumetric images, and by the 'marching lines' algorithm. The recovered lines are then approximated by splines curves, to compute at each point a number of differential invariants. Matching is finally performed by a new geometric hashing method. The whole chain is now completely automatic, and provides extremely robust and accurate results, even in the presence of severe occlusions. In this paper, we briefly describe the whole chain of processes, already presented to evaluate the accuracy of the approach on a couple of CT-scan images of a skull containing external markers.

  9. Is 3D printing safe? Analysis of the thermal treatment of thermoplastics: ABS, PLA, PET, and nylon.

    Wojtyła, Szymon; Klama, Piotr; Baran, Tomasz

    2017-02-06

    The fast development of low-cost desktop three-dimensional (3D) printers has made those devices widely accessible for goods manufacturing at home. However, is it safe? Users may belittle the effects or influences of pollutants (organic compounds and ultrafine particles) generated by the devices in question. Within the scope of this study, the authors attempt to investigate thermal decomposition of the following commonly used, commercially available thermoplastic filaments: acrylonitrile-butadiene-styrene (ABS), polylactic acid (PLA), polyethylene terephthalate (PET), and nylon. Thermogravimetric analysis has shown the detailed thermal patterns of their behavior upon increasing temperature in neutral atmosphere, while GC analysis of organic vapors emitted during the process of heating thermoplastics have made it possible to obtain crucial pieces of information about the toxicity of 3D printing process. The conducted study has shown that ABS is significantly more toxic than PLA. The emission of volatile organic compounds (VOC) has been in the range of 0.50 μmol/h. Styrene has accounted for more than 30% of total VOC emitted from ABS, while for PLA, methyl methacrylate has been detected as the predominant compound (44% of total VOCs emission). Moreover, the authors have summarized available or applicable methods that can eliminate formed pollutants and protect the users of 3D printers. This paper summarizes theoretical knowledge on thermal degradation of polymers used for 3D printers and shows results of authors' investigation, as well as presents forward-looking solutions that may increase the safety of utilization of 3D printers.

  10. Combination of thermal extrusion printing and ultrafast laser fabrication for the manufacturing of 3D composite scaffolds

    Balčiūnas, Evaldas; Lukoševičius, Laurynas; Mackevičiūtė, Dovilė; Rekštytė, Sima; Rutkūnas, Vygandas; Paipulas, Domas; Stankevičiūtė, Karolina; Baltriukienė, Daiva; Bukelskienė, Virginija; Piskarskas, Algis P.; Malinauskas, Mangirdas

    2014-03-01

    We present a novel approach to manufacturing 3D microstructured composite scaffolds for tissue engineering applications. A thermal extrusion 3D printer - a simple, low-cost tabletop device enabling rapid materialization of CAD models in plastics - was used to produce cm-scale microporous scaffolds out of polylactic acid (PLA). The fabricated objects were subsequently immersed in a photosensitive monomer solution and direct laser writing technique (DLW) was used to refine its inner structure by fabricating a fine mesh inside the previously produced scaffold. In addition, a composite material structure out of four different materials fabricated via DLW is presented. This technique, empowered by ultrafast lasers allows 3D structuring with high spatial resolution in a great variety of photosensitive materials. A composite scaffold made of distinct materials and periodicities is acquired after the development process used to wash out non-linked monomers. Another way to modify the 3D printed PLA surfaces was also demonstrated - ablation with femtosecond laser beam. Structure geometry on macro- to micro- scales could be finely tuned by combining these fabrication techniques. Such artificial 3D substrates could be used for cell growth or as biocompatible-biodegradable implants. To our best knowledge, this is the first experimental demonstration showing the creation of composite 3D scaffolds using convenient 3D printing combined with DLW. This combination of distinct material processing techniques enables rapid fabrication of diverse functional micro-featured and integrated devices. Hopefully, the proposed approach will find numerous applications in the field of tissue engineering, as well as in microelectromechanical systems, microfluidics, microoptics and others.

  11. Automotive Underhood Thermal Management Analysis Using 3-D Coupled Thermal-Hydrodynamic Computer Models: Thermal Radiation Modeling

    Pannala, S; D' Azevedo, E; Zacharia, T

    2002-02-26

    The goal of the radiation modeling effort was to develop and implement a radiation algorithm that is fast and accurate for the underhood environment. As part of this CRADA, a net-radiation model was chosen to simulate radiative heat transfer in an underhood of a car. The assumptions (diffuse-gray and uniform radiative properties in each element) reduce the problem tremendously and all the view factors for radiation thermal calculations can be calculated once and for all at the beginning of the simulation. The cost for online integration of heat exchanges due to radiation is found to be less than 15% of the baseline CHAD code and thus very manageable. The off-line view factor calculation is constructed to be very modular and has been completely integrated to read CHAD grid files and the output from this code can be read into the latest version of CHAD. Further integration has to be performed to accomplish the same with STAR-CD. The main outcome of this effort is to obtain a highly scalable and portable simulation capability to model view factors for underhood environment (for e.g. a view factor calculation which took 14 hours on a single processor only took 14 minutes on 64 processors). The code has also been validated using a simple test case where analytical solutions are available. This simulation capability gives underhood designers in the automotive companies the ability to account for thermal radiation - which usually is critical in the underhood environment and also turns out to be one of the most computationally expensive components of underhood simulations. This report starts off with the original work plan as elucidated in the proposal in section B. This is followed by Technical work plan to accomplish the goals of the project in section C. In section D, background to the current work is provided with references to the previous efforts this project leverages on. The results are discussed in section 1E. This report ends with conclusions and future scope of

  12. A comprehensive evaluation of the PRESAGE/optical-CT 3D dosimetry system

    Sakhalkar, H. S.; Adamovics, J.; Ibbott, G.; Oldham, M. [Department of Radiation Oncology Physics, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Chemistry and Biology, Rider University, Lawrenceville, New Jersey 08648 (United States); Department of Radiation Physics, M. D. Anderson Cancer Center, Houston, Texas 77030 (United States); Department of Radiation Oncology Physics, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2009-01-15

    This work presents extensive investigations to evaluate the robustness (intradosimeter consistency and temporal stability of response), reproducibility, precision, and accuracy of a relatively new 3D dosimetry system comprising a leuco-dye doped plastic 3D dosimeter (PRESAGE) and a commercial optical-CT scanner (OCTOPUS 5x scanner from MGS Research, Inc). Four identical PRESAGE 3D dosimeters were created such that they were compatible with the Radiologic Physics Center (RPC) head-and-neck (H and N) IMRT credentialing phantom. Each dosimeter was irradiated with a rotationally symmetric arrangement of nine identical small fields (1x3 cm{sup 2}) impinging on the flat circular face of the dosimeter. A repetitious sequence of three dose levels (4, 2.88, and 1.28 Gy) was delivered. The rotationally symmetric treatment resulted in a dose distribution with high spatial variation in axial planes but only gradual variation with depth along the long axis of the dosimeter. The significance of this treatment was that it facilitated accurate film dosimetry in the axial plane, for independent verification. Also, it enabled rigorous evaluation of robustness, reproducibility and accuracy of response, at the three dose levels. The OCTOPUS 5x commercial scanner was used for dose readout from the dosimeters at daily time intervals. The use of improved optics and acquisition technique yielded substantially improved noise characteristics (reduced to {approx}2%) than has been achieved previously. Intradosimeter uniformity of radiochromic response was evaluated by calculating a 3D gamma comparison between each dosimeter and axially rotated copies of the same dosimeter. This convenient technique exploits the rotational symmetry of the distribution. All points in the gamma comparison passed a 2% difference, 1 mm distance-to-agreement criteria indicating excellent intradosimeter uniformity even at low dose levels. Postirradiation, the dosimeters were all found to exhibit a slight increase in

  13. Role of 3D-CT for orthodontic and ENT evaluation in Goldenhar syndrome.

    Saccomanno, S; Greco, F; D'Alatri, L; De Corso, E; Pandolfini, M; Sergi, B; Pirronti, T; Deli, R

    2014-08-01

    Goldenhar syndrome is a congenital condition that includes anomalies of the derivatives of the first and second brachial arches, vertebral defects and ocular abnormalities. It is also known as oculo-auriculo-vertebrale syndrome (OAVS), hemifacial microsomia, or first or second brachial arch syndrome. It was first described by Van Duyse in 1882 and better studied by M. Goldenhar in 1952. Its treatment requires a multidisciplinary approach. Herein, we describe the value of 3D-CT evaluation in a patient with Goldenhar syndrome, with particular regard to planning diagnostic and therapeutic approach. A 7-year-old boy with Goldenhar syndrome with definite post-natal genetic diagnosis was referred to our Department of Radiology for neuroimaging of the temporal bone. By 3D-CT evaluation of this young patient we observed the asymmetry of the condyles with the right one dysmorphic, short and wide; the auricle of the right ear was replaced by a dysmorphic rough; the right middle ear had a hypoplastic tympanic cavity and the internal auditory canal of right ear was atresic. In our experience, 3D-CT is a powerful diagnostic instrument and offers many advantages: volumetric reproduction of cranium and soft tissues, no overlap of anatomic parts that limits the visibility of various structures, high precision and assurance of images, and a constant and easily reproducible reference system. In our case, 3D-CT offered a very complete evaluation of all malformations of mandibular and temporal bone that characterize this syndrome and representing an important step for ENT and orthodontic therapeutic approaches.

  14. 3-D TECATE/BREW: Thermal, stress, and birefringent ray-tracing codes for solid-state laser design

    Gelinas, R. J.; Doss, S. K.; Nelson, R. G.

    1994-07-01

    This report describes the physics, code formulations, and numerics that are used in the TECATE (totally Eulerian code for anisotropic thermo-elasticity) and BREW (birefringent ray-tracing of electromagnetic waves) codes for laser design. These codes resolve thermal, stress, and birefringent optical effects in 3-D stationary solid-state systems. This suite of three constituent codes is a package referred to as LASRPAK.

  15. Two-dimensional evaluation of 3D needled Cf/SiC composite fiber bundle surface

    Wei, Jinhua; Lin, Bin; Cao, Xiaoyan; Zhang, Xiaofeng; Fang, Sheng

    2015-11-01

    The variations of fiber bundle surface microstructure have direct influence on the material performance, especially the friction and wear properties. Therefore, fiber bundle is the smallest evaluation unit of Cf/SiC composite surface. However, due to the anisotropy and inhomogeneity of Cf/SiC composite, it is difficult to evaluate the surface characteristics. Researchers think that two-dimensional evaluation is not suitable for the composites surface assessment any more because of its complex composition and varied surface structure. In this paper, a novel method is introduced for the evaluation of 3D needled Cf/SiC composite fiber bundle surface. On the level of Cf/SiC composite fiber bundle surface, two-dimensional evaluation method is adopted, with which the fiber bundle surface quality can be quantitatively evaluated by the two-dimensional surface roughness Ra. As long as the extracted surface profiles averagely distributed on Cf/SiC composite fiber bundle surface, with appropriate sampling length and sampling number, the mean value of Ra can estimate the whole surface roughness, thus reflecting the roughness degree of surface accurately. This study not only benefits the detection of 3D needled Cf/SiC composite fiber bundle surface quality, and lays a foundation on the evaluation of material functional features in further. And it corresponds to the convenient application in engineering practice.

  16. Error Evaluation in a Stereovision-Based 3D Reconstruction System

    Kohler Sophie

    2010-01-01

    Full Text Available The work presented in this paper deals with the performance analysis of the whole 3D reconstruction process of imaged objects, specifically of the set of geometric primitives describing their outline and extracted from a pair of images knowing their associated camera models. The proposed analysis focuses on error estimation for the edge detection process, the starting step for the whole reconstruction procedure. The fitting parameters describing the geometric features composing the workpiece to be evaluated are used as quality measures to determine error bounds and finally to estimate the edge detection errors. These error estimates are then propagated up to the final 3D reconstruction step. The suggested error analysis procedure for stereovision-based reconstruction tasks further allows evaluating the quality of the 3D reconstruction. The resulting final error estimates enable lastly to state if the reconstruction results fulfill a priori defined criteria, for example, fulfill dimensional constraints including tolerance information, for vision-based quality control applications for example.

  17. Evaluation of Large Intracranial Aneurysms with Cine MRA and 3D Contrast-Enhanced MRA

    朱文珍; 冯定义; 漆剑频; 夏黎明; 王承缘

    2004-01-01

    Summary: The value of combined application of both ECG-gated cine MRA and 3D-CEMRA in the detection of large intracranial aneurysms was evaluated and the findings were compared with those of conventional MRA and DSA. Twenty-four patients with 26 large intraeranial aneurysms underwent MRI and DSA. All these aneurysms, diameter from 15 to 39 mm, were located at internal cerebral artery (n = 12), vertebral artery (n = 3), basilar artery (n = 4), anterior cerebral artery (n =2), middle cerebral artery (n=2), anterior communicate artery (n=2) and posterior communicate artery (n= 1). Thirteen cases of hematoma or cavernoma were studied as control group. All patients were examined on GE 1.5T MR system. ECG-gated eine MRA was performed with 2D multi-phase fast gradient-recalled echo sequence in a single section. All the images were analyzed with signal intensity VS time curve for differentiating intraaneurysmal blood flow from static tissue.The results were analzsed by statistic "t" test. 3D-CEMRA was performed with spoiled gradient-recalled echo and one dose of Gd-DTPA. All data was processed with multi-plannar reformat (MPR)and tomography for the demonstration of aneurysms in detail. All 26 aneurysms were demonstrated successfully by combined application of both cine MRA and 3D-CEMRA. Compared to DSA and conventional 3D-MOTSA, its sensitivity and specificity figures were both 100 %. Cine MRA could differentiate the blood flow from the static tissue. The intensity VS time curves of intraaneurysmal blood flow offered fluctuating form and average signal change between systole and diastole period was about 89.8±37.4; However, under the control group, intraaneurysmal thrombus or cerebral hemorrhage or eavernomas had no significant signal change and the curves offered steady form with the average signal change being about 8.2 ± 6. 3. There was statistically significant difference between the intraaneurysmal blood flow and static tissue (P= 0. 025, <0.05). 3D-CEMRA was very

  18. A Continuous 3D-Graphene Network to Overcome Threshold Issues and Contact Resistance in Thermally Conductive Graphene Nanocomposites

    Federico Conrado

    2017-01-01

    Full Text Available In order to overcome thermal resistance issues in polymeric matrix composites, self-standing graphene aerogels were synthetized and infiltrated with an epoxy resin, in order to create conductive preferential pathways through which heat can be easily transported. These continuous highly thermally conductive 3D-structures show, due to the high interconnection degree of graphene flakes, enhanced transport properties. Two kinds of aerogels were investigated, obtained by hydrothermal synthesis (HS and ice-templated direct freeze synthesis (DFS. Following HS method an isotropic structure is obtained, and following DFS method instead an anisotropic arrangement of graphene flakes results. The density of the structure can be tuned leading to a different amount of graphene inside the final composite. The residual oxygen, known to be detrimental to thermal properties, was removed by thermal treatment before the infiltration process. With 1,25 wt.% of graphene, using HS method, the thermal conductivity of the polymeric resin was increased by 80%, suggesting that this technique is a valid route to improve the thermal performance of graphene-based composites. When preferential orientation of the filler was present (DFS case, thermal conductivity was increased more than 25% with a graphene content of only 0,27 wt.%, demonstrating that oriented structures can further improve the thermal transport efficiency.

  19. Comparison of a small-scale 3D PCM thermal control model with a validated 2D PCM thermal control model

    Huang, M.J.; Eames, P.C. [Centre for Sustainable Technologies, School of the Built Environment, University of Ulster, Newtownabbey, BT37 0QB, N.Ireland (United Kingdom); Norton, B. [FOCAS Institute, Dublin Institute of Technology, Aungier Street, Dublin 2 (Ireland)

    2006-08-15

    A three-dimensional (3D) numerical model was developed to simulate the use of a phase change material linked to a photovoltaic (PV) system to control the temperature rise of the PV cells. The model can be used to predict temperatures, velocity fields and vortex formation within the system. The 3D predictions have been compared with those from a previously developed experimental validated two-dimensional (2D) finite-volume heat transfer model conjugated hydro-dynamically to solve the Navier-Stokes and energy equations. It was found that for the systems simulated with appropriate boundary conditions, the 2D model predictions compare well with those of the 3D model. The 3D model was used to predict the temperature distributions when the heat transfer to the phase change material was enhanced by high thermal conductivity pin fins. (author)

  20. Heavy Ion Induced SEU Sensitivity Evaluation of 3D Integrated SRAMs

    Cao, Xuebing; Huo, Mingxue; Wang, Tianqi; Li, Anlong; Qi, Chunhua; Wang, Jinxiang

    2016-01-01

    Heavy ions induced single event upset (SEU) sensitivity of three-dimensional integrated SRAMs are evaluated by using Monte Carlo sumulation methods based on Geant4. The cross sections of SEUs and Multi Cell Upsets (MCUs) for 3D SRAM are simulated by using heavy ions with different energies and LETs. The results show that the sensitivity of different die of 3D SRAM has obvious discrepancies at low LET. Average percentage of MCUs of 3D SRAMs rises from 17.2% to 32.95% when LET increases from 42.19 MeV cm2/mg to 58.57MeV cm2/mg. As for a certain LET, the percentage of MCUs shows a notable distinction between face-to-face structure and back-to-face structure. For back-to-face structure, the percentage of MCUs increases with the deeper die. However, the face-to-face die presents the relatively low percentage of MCUs. The comparison of SEU cross sections for planar SRAMs and experiment data are conducted to indicate the effectiveness of our simulation method. Finally, we compare the upset cross sections of planar p...

  1. Non-destructive 3D shape measurement of transparent and black objects with thermal fringes

    Brahm, Anika; Rößler, Conrad; Dietrich, Patrick; Heist, Stefan; Kühmstedt, Peter; Notni, Gunther

    2016-05-01

    Fringe projection is a well-established optical method for the non-destructive contactless three-dimensional (3D) measurement of object surfaces. Typically, fringe sequences in the visible wavelength range (VIS) are projected onto the surfaces of objects to be measured and are observed by two cameras in a stereo vision setup. The reconstruction is done by finding corresponding pixels in both cameras followed by triangulation. Problems can occur if the properties of some materials disturb the measurements. If the objects are transparent, translucent, reflective, or strongly absorbing in the VIS range, the projected patterns cannot be recorded properly. To overcome these challenges, we present a new alternative approach in the infrared (IR) region of the electromagnetic spectrum. For this purpose, two long-wavelength infrared (LWIR) cameras (7.5 - 13 μm) are used to detect the emitted heat radiation from surfaces which is induced by a pattern projection unit driven by a CO2 laser (10.6 μm). Thus, materials like glass or black objects, e.g. carbon fiber materials, can be measured non-destructively without the need of any additional paintings. We will demonstrate the basic principles of this heat pattern approach and show two types of 3D systems based on a freeform mirror and a GOBO wheel (GOes Before Optics) projector unit.

  2. Evaluation of absolute phase for 3D profile measurement using fringe projection

    Mengtao Huang; Zhuangde Jiang; Bing Li; Suping Fang

    2006-01-01

    A new method of absolute phase evaluation for three-dimensional (3D) profile measurement using fringe projection is presented, which combines the gray code and the phase shift technique. Two kinds of fringe patterns are projected onto the object surface respectively, one is sinusoidal intensity distribution used for phase demodulation and the other is gray code fringe pattern for unwrapping. These images are acquired by camera and stored into computer. The absolute phase is obtained by analyzing these images. The validity of this method is verified experimentally. The method is superior to other phase unwrapping methods.

  3. 3D COMSOL Simulations for Thermal Deflection of HFIR Fuel Plate in the "Cheverton-Kelley" Experiments

    Jain, Prashant K [ORNL; Freels, James D [ORNL; Cook, David Howard [ORNL

    2012-08-01

    Three dimensional simulation capabilities are currently being developed at Oak Ridge National Laboratory using COMSOL Multiphysics, a finite element modeling software, to investigate thermal expansion of High Flux Isotope Reactor (HFIR) s low enriched uranium fuel plates. To validate simulations, 3D models have also been developed for the experimental setup used by Cheverton and Kelley in 1968 to investigate the buckling and thermal deflections of HFIR s highly enriched uranium fuel plates. Results for several simulations are presented in this report, and comparisons with the experimental data are provided when data are available. A close agreement between the simulation results and experimental findings demonstrates that the COMSOL simulations are able to capture the thermal expansion physics accurately and that COMSOL could be deployed as a predictive tool for more advanced computations at realistic HFIR conditions to study temperature-induced fuel plate deflection behavior.

  4. Neutronic and thermal-hydraulic coupling for 3D reactor core modeling combining MCB and fluent

    Królikowski Igor P.

    2015-09-01

    Full Text Available Three-dimensional simulations of neutronics and thermal hydraulics of nuclear reactors are a tool used to design nuclear reactors. The coupling of MCB and FLUENT is presented, MCB allows to simulate neutronics, whereas FLUENT is computational fluid dynamics (CFD code. The main purpose of the coupling is to exchange data such as temperature and power profile between both codes. Temperature required as an input parameter for neutronics is significant since cross sections of nuclear reactions depend on temperature. Temperature may be calculated in thermal hydraulics, but this analysis needs as an input the power profile, which is a result from neutronic simulations. Exchange of data between both analyses is required to solve this problem. The coupling is a better solution compared to the assumption of estimated values of the temperatures or the power profiles; therefore the coupled analysis was created. This analysis includes single transient neutronic simulation and several steady-state thermal simulations. The power profile is generated in defined points in time during the neutronic simulation for the thermal analysis to calculate temperature. The coupled simulation gives information about thermal behavior of the reactor, nuclear reactions in the core, and the fuel evolution in time. Results show that there is strong influence of neutronics on thermal hydraulics. This impact is stronger than the impact of thermal hydraulics on neutronics. Influence of the coupling on temperature and neutron multiplication factor is presented. The analysis has been performed for the ELECTRA reactor, which is lead-cooled fast reactor concept, where the coolant fl ow is generated only by natural convection

  5. The Kenya rift revisited: insights into lithospheric strength through data-driven 3-D gravity and thermal modelling

    Sippel, Judith; Meeßen, Christian; Cacace, Mauro; Mechie, James; Fishwick, Stewart; Heine, Christian; Scheck-Wenderoth, Magdalena; Strecker, Manfred R.

    2017-01-01

    We present three-dimensional (3-D) models that describe the present-day thermal and rheological state of the lithosphere of the greater Kenya rift region aiming at a better understanding of the rift evolution, with a particular focus on plume-lithosphere interactions. The key methodology applied is the 3-D integration of diverse geological and geophysical observations using gravity modelling. Accordingly, the resulting lithospheric-scale 3-D density model is consistent with (i) reviewed descriptions of lithological variations in the sedimentary and volcanic cover, (ii) known trends in crust and mantle seismic velocities as revealed by seismic and seismological data and (iii) the observed gravity field. This data-based model is the first to image a 3-D density configuration of the crystalline crust for the entire region of Kenya and northern Tanzania. An upper and a basal crustal layer are differentiated, each composed of several domains of different average densities. We interpret these domains to trace back to the Precambrian terrane amalgamation associated with the East African Orogeny and to magmatic processes during Mesozoic and Cenozoic rifting phases. In combination with seismic velocities, the densities of these crustal domains indicate compositional differences. The derived lithological trends have been used to parameterise steady-state thermal and rheological models. These models indicate that crustal and mantle temperatures decrease from the Kenya rift in the west to eastern Kenya, while the integrated strength of the lithosphere increases. Thereby, the detailed strength configuration appears strongly controlled by the complex inherited crustal structure, which may have been decisive for the onset, localisation and propagation of rifting.

  6. Development and Evaluation of High-Performance Decorrelation Algorithms for the Nonalternating 3D Wavelet Transform

    Quiles FJ

    2007-01-01

    Full Text Available We introduce and evaluate the implementations of three parallel video-sequences decorrelation algorithms. The proposed algorithms are based on the nonalternating classic three-dimensional wavelet transform (3D-WT. The parallel implementations of the algorithms are developed and tested on a shared memory system, an SGI origin 3800 supercomputer making use of a message-passing paradigm. We evaluate and analyze the performance of the implementations in terms of the response time and speed-up factor by varying the number of processors and various video coding parameters. The key points enabling the development of highly efficient implementations rely on the partitioning of the video sequences into groups of frames and a workload distribution strategy supplemented by the use of parallel I/O primitives, for better exploiting the inherent features of the application and computing platform. We also evaluate the effectiveness of our algorithms in terms of the first-order entropy.

  7. Some Experiences in 3D Laser Scanning for Assisting Restoration and Evaluating Damage in Cultural Heritage

    Fuentes, L. M.; Finat, Javier; Fernández-Martin, J. J.; Martínez, J.; SanJose, J. I.

    The recent incorporation of laser devices provides advanced tools for assisting the conservation and restoration of Cultural Heritage. It is necessary to have as complete as possible understanding of the object state before evaluating or defining the reach of the restoration process. Thus, a special effort is devoted to surveying, measuring and generating a high-resolution 3D model prior to restoration planning. This work presents results of several experiments performed on damaged pieces for evaluation purposes in Cultural Heritage. Some software tools are applied for carving-work analysis, conservation-state monitoring, and simulation of weathering processes for evaluating temporal changes. In all cases considered, a high resolution information capture has been performed with a laser scanner, the Minolta 910. Our approach is flexible enough to be adapted to other kinds of pieces or Cultural Heritage artefacts, in order to provide an assessment for intervention planning in conservation and restoration tasks.

  8. Evaluation of PC-ISO for customized, 3D printed, gynecologic 192Ir HDR brachytherapy applicators.

    Cunha, J Adam M; Mellis, Katherine; Sethi, Rajni; Siauw, Timmy; Sudhyadhom, Atchar; Garg, Animesh; Goldberg, Ken; Hsu, I-Chow; Pouliot, Jean

    2015-01-01

    The purpose of this study was to evaluate the radiation attenuation properties of PC-ISO, a commercially available, biocompatible, sterilizable 3D printing material, and its suitability for customized, single-use gynecologic (GYN) brachytherapy applicators that have the potential for accurate guiding of seeds through linear and curved internal channels. A custom radiochromic film dosimetry apparatus was 3D-printed in PC-ISO with a single catheter channel and a slit to hold a film segment. The apparatus was designed specifically to test geometry pertinent for use of this material in a clinical setting. A brachytherapy dose plan was computed to deliver a cylindrical dose distribution to the film. The dose plan used an 192Ir source and was normalized to 1500 cGy at 1 cm from the channel. The material was evaluated by comparing the film exposure to an identical test done in water. The Hounsfield unit (HU) distributions were computed from a CT scan of the apparatus and compared to the HU distribution of water and the HU distribution of a commercial GYN cylinder applicator. The dose depth curve of PC-ISO as measured by the radiochromic film was within 1% of water between 1 cm and 6 cm from the channel. The mean HU was -10 for PC-ISO and -1 for water. As expected, the honeycombed structure of the PC-ISO 3D printing process created a moderate spread of HU values, but the mean was comparable to water. PC-ISO is sufficiently water-equivalent to be compatible with our HDR brachytherapy planning system and clinical workflow and, therefore, it is suitable for creating custom GYN brachytherapy applicators. Our current clinical practice includes the use of custom GYN applicators made of commercially available PC-ISO when doing so can improve the patient's treatment. PACS number: none.

  9. Evaluation of PC-ISO for customized, 3D Printed, gynecologic 192-Ir HDR brachytherapy applicators.

    Cunha, J Adam M; Mellis, Katherine; Sethi, Rajni; Siauw, Timmy; Sudhyadhom, Atchar; Garg, Animesh; Goldberg, Ken; Hsu, I-Chow; Pouliot, Jean

    2015-01-08

    The purpose of this study was to evaluate the radiation attenuation properties of PC-ISO, a commercially available, biocompatible, sterilizable 3D printing material, and its suitability for customized, single-use gynecologic (GYN) brachytherapy applicators that have the potential for accurate guiding of seeds through linear and curved internal channels. A custom radiochromic film dosimetry apparatus was 3D-printed in PC-ISO with a single catheter channel and a slit to hold a film segment. The apparatus was designed specifically to test geometry pertinent for use of this material in a clinical setting. A brachytherapy dose plan was computed to deliver a cylindrical dose distribution to the film. The dose plan used an 192Ir source and was normalized to 1500 cGy at 1 cm from the channel. The material was evaluated by comparing the film exposure to an identical test done in water. The Hounsfield unit (HU) distributions were computed from a CT scan of the apparatus and compared to the HU distribution of water and the HU distribution of a commercial GYN cylinder applicator. The dose depth curve of PC-ISO as measured by the radiochromic film was within 1% of water between 1 cm and 6 cm from the channel. The mean HU was -10 for PC-ISO and -1 for water. As expected, the honeycombed structure of the PC-ISO 3D printing process created a moderate spread of HU values, but the mean was comparable to water. PC-ISO is sufficiently water-equivalent to be compatible with our HDR brachytherapy planning system and clinical workflow and, therefore, it is suitable for creating custom GYN brachytherapy applicators. Our current clinical practice includes the use of custom GYN applicators made of commercially available PC-ISO when doing so can improve the patient's treatment. 

  10. Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

    Himanshu PATHAK[1; Akhilendra SINGH[2; I.V. SINGH[3; S. K. YADAV[3

    2015-01-01

    This paper deals with the fatigue crack growth simulations of three-dimensional linear elastic cracks by XFEM under cyclic thermal load. Both temperature and displacement approximations are extrinsically enriched by Heaviside and crack front enrichment functions. Crack growth is modelled by successive linear extensions, and the end points of these linear extensions are joined by cubic spline segments to obtain a modified crack front. Different crack geometries such as planer, non-planer and arbitrary spline shape cracks are simulated under thermal shock, adiabatic and isothermal loads to reveal the sturdiness and versatility of the XFEM approach.

  11. Thermal Resistance across Interfaces Comprising Dimensionally Mismatched Carbon Nanotube-Graphene Junctions in 3D Carbon Nanomaterials

    Jungkyu Park

    2014-01-01

    Full Text Available In the present study, reverse nonequilibrium molecular dynamics is employed to study thermal resistance across interfaces comprising dimensionally mismatched junctions of single layer graphene floors with (6,6 single-walled carbon nanotube (SWCNT pillars in 3D carbon nanomaterials. Results obtained from unit cell analysis indicate the presence of notable interfacial thermal resistance in the out-of-plane direction (along the longitudinal axis of the SWCNTs but negligible resistance in the in-plane direction along the graphene floor. The interfacial thermal resistance in the out-of-plane direction is understood to be due to the change in dimensionality as well as phonon spectra mismatch as the phonons propagate from SWCNTs to the graphene sheet and then back again to the SWCNTs. The thermal conductivity of the unit cells was observed to increase nearly linearly with an increase in cell size, that is, pillar height as well as interpillar distance, and approaches a plateau as the pillar height and the interpillar distance approach the critical lengths for ballistic thermal transport in SWCNT and single layer graphene. The results indicate that the thermal transport characteristics of these SWCNT-graphene hybrid structures can be tuned by controlling the SWCNT-graphene junction characteristics as well as the unit cell dimensions.

  12. The Performance Evaluation of Multi-Image 3d Reconstruction Software with Different Sensors

    Mousavi, V.; Khosravi, M.; Ahmadi, M.; Noori, N.; Naveh, A. Hosseini; Varshosaz, M.

    2015-12-01

    Today, multi-image 3D reconstruction is an active research field and generating three dimensional model of the objects is one the most discussed issues in Photogrammetry and Computer Vision that can be accomplished using range-based or image-based methods. Very accurate and dense point clouds generated by range-based methods such as structured light systems and laser scanners has introduced them as reliable tools in the industry. Image-based 3D digitization methodologies offer the option of reconstructing an object by a set of unordered images that depict it from different viewpoints. As their hardware requirements are narrowed down to a digital camera and a computer system, they compose an attractive 3D digitization approach, consequently, although range-based methods are generally very accurate, image-based methods are low-cost and can be easily used by non-professional users. One of the factors affecting the accuracy of the obtained model in image-based methods is the software and algorithm used to generate three dimensional model. These algorithms are provided in the form of commercial software, open source and web-based services. Another important factor in the accuracy of the obtained model is the type of sensor used. Due to availability of mobile sensors to the public, popularity of professional sensors and the advent of stereo sensors, a comparison of these three sensors plays an effective role in evaluating and finding the optimized method to generate three-dimensional models. Lots of research has been accomplished to identify a suitable software and algorithm to achieve an accurate and complete model, however little attention is paid to the type of sensors used and its effects on the quality of the final model. The purpose of this paper is deliberation and the introduction of an appropriate combination of a sensor and software to provide a complete model with the highest accuracy. To do this, different software, used in previous studies, were compared and

  13. Thermal-Aware Design and Runtime Management of 3D Stacked Multiprocessors

    Kumar, S.S.

    2015-01-01

    The sustained increase in computational performance demanded by next-generation applications drives the increasing core counts of modern multiprocessor systems. However, in the dark silicon era, the performance levels and integration density of such systems is limited by thermal constraints of their

  14. Verification of an Acoustic 3D BEM with Visco-Thermal Losses

    Juhl, Peter Møller; Cutanda Henriquez, Vicente

    2013-01-01

    Sound waves propagating in the interior of devices such as acoustic transducers, hearing aids and mobile phones undergo a significant amount of losses due to viscous and thermal effects. In some cases like microphones, the performance of the device even relies on controlling these loss mechanisms...

  15. Implementation of an Acoustic 3D BEM with Visco-Thermal Losses

    Cutanda Henriquez, Vicente; Juhl, Peter Møller

    2013-01-01

    There is an increasing need in industry for numerical acoustic models including viscous and thermal losses of sound in air. Small devices such as couplers, microphones, mobile phones and hearing aids contain small cavities and passages where wave propagation cannot be assumed to be lossless...

  16. Evaluation of helper-dependent canine adenovirus vectors in a 3D human CNS model.

    Simão, D; Pinto, C; Fernandes, P; Peddie, C J; Piersanti, S; Collinson, L M; Salinas, S; Saggio, I; Schiavo, G; Kremer, E J; Brito, C; Alves, P M

    2016-01-01

    Gene therapy is a promising approach with enormous potential for treatment of neurodegenerative disorders. Viral vectors derived from canine adenovirus type 2 (CAV-2) present attractive features for gene delivery strategies in the human brain, by preferentially transducing neurons, are capable of efficient axonal transport to afferent brain structures, have a 30-kb cloning capacity and have low innate and induced immunogenicity in preclinical tests. For clinical translation, in-depth preclinical evaluation of efficacy and safety in a human setting is primordial. Stem cell-derived human neural cells have a great potential as complementary tools by bridging the gap between animal models, which often diverge considerably from human phenotype, and clinical trials. Herein, we explore helper-dependent CAV-2 (hd-CAV-2) efficacy and safety for gene delivery in a human stem cell-derived 3D neural in vitro model. Assessment of hd-CAV-2 vector efficacy was performed at different multiplicities of infection, by evaluating transgene expression and impact on cell viability, ultrastructural cellular organization and neuronal gene expression. Under optimized conditions, hd-CAV-2 transduction led to stable long-term transgene expression with minimal toxicity. hd-CAV-2 preferentially transduced neurons, whereas human adenovirus type 5 (HAdV5) showed increased tropism toward glial cells. This work demonstrates, in a physiologically relevant 3D model, that hd-CAV-2 vectors are efficient tools for gene delivery to human neurons, with stable long-term transgene expression and minimal cytotoxicity.

  17. In Vitro Biological Evaluation of 3-D Hydroxyapatite/Collagen (50/50 wt. (% Scaffolds

    Doris Moura Campos

    2012-02-01

    Full Text Available Hydroxyapatite-collagen (HA/Col composites are potential scaffolds for bone tissue engineering. In this work, three-dimensional (3-D HA/Col (50/50 wt. (% scaffolds were synthesized using a self-assembly method and cross-linked with a 0.125% glutaraldehyde solution. Scaffolds were evaluated in vitro by cytotoxicity testing using MC3T3 cells; proliferation and differentiation were studied using STRO-1A human stromal cells for up to 21 days. Morphological and histological examinations showed a fibrous structure with a good distribution and homogeneous HA particles distribution. By thermogravimetric analysis, a ratio of 1.2 between inorganic and organic phase was found. The scaffolds presented no cytotoxicity when evaluated using three different parameters of cell survival and integrity: 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl] -2H-tetrazolium-5-carboxanilide (XTT, Neutral Red (NR and Crystal Violet Dye Elution (CVDE. STRO-1A cells were found to adhere, proliferate and differentiate on the 3-D scaffold, but limited cell penetration was observed.

  18. MAL Daylight Photodynamic Therapy for Actinic Keratosis: Clinical and Imaging Evaluation by 3D Camera.

    Cantisani, Carmen; Paolino, Giovanni; Pellacani, Giovanni; Didona, Dario; Scarno, Marco; Faina, Valentina; Gobello, Tommaso; Calvieri, Stefano

    2016-07-11

    Non-melanoma skin cancer is the most common skin cancer with an incidence that varies widely worldwide. Among them, actinic keratosis (AK), considered by some authors as in situ squamous cell carcinoma (SCC), are the most common and reflect an abnormal multistep skin cell development due to the chronic ultraviolet (UV) light exposure. No ideal treatment exists, but the potential risk of their development in a more invasive form requires prompt treatment. As patients usually present with multiple AK on fields of actinic damage, there is a need for effective, safe, simple and short treatments which allow the treatment of large areas. To achieve this, daylight photodynamic therapy (DL-PDT) is an innovative treatment for multiple mild actinic keratosis, well tolerated by patients. Patients allocated to the PDT unit, affected by multiple mild-moderate and severe actinic keratosis on sun-exposed areas treated with DL-PDT, were clinically evaluated at baseline and every three months with an Antera 3D, Miravex(©) camera. Clinical and 3D images were performed at each clinical check almost every three months. In this retrospective study, 331 patients (56.7% male, 43.3% female) were treated with DL-PDT. We observed a full clearance in more than two-thirds of patients with one or two treatments. Different responses depend on the number of lesions and on their severity; for patients with 1-3 lesions and with grade I or II AK, a full clearance was reached in 85% of cases with a maximum of two treatments. DL-PDT in general improved skin tone and erased sun damage. Evaluating each Antera 3D images, hemoglobin concentration and pigmentation, a skin color and tone improvement in 310 patients was observed. DL-PDT appears as a promising, effective, simple, tolerable and practical treatment for actinic damage associated with AK, and even treatment of large areas can be with little or no pain. The 3D imaging allowed for quantifying in real time the aesthetic benefits of DL

  19. MAL Daylight Photodynamic Therapy for Actinic Keratosis: Clinical and Imaging Evaluation by 3D Camera

    Carmen Cantisani

    2016-07-01

    Full Text Available Non-melanoma skin cancer is the most common skin cancer with an incidence that varies widely worldwide. Among them, actinic keratosis (AK, considered by some authors as in situ squamous cell carcinoma (SCC, are the most common and reflect an abnormal multistep skin cell development due to the chronic ultraviolet (UV light exposure. No ideal treatment exists, but the potential risk of their development in a more invasive form requires prompt treatment. As patients usually present with multiple AK on fields of actinic damage, there is a need for effective, safe, simple and short treatments which allow the treatment of large areas. To achieve this, daylight photodynamic therapy (DL-PDT is an innovative treatment for multiple mild actinic keratosis, well tolerated by patients. Patients allocated to the PDT unit, affected by multiple mild−moderate and severe actinic keratosis on sun-exposed areas treated with DL-PDT, were clinically evaluated at baseline and every three months with an Antera 3D, Miravex© camera. Clinical and 3D images were performed at each clinical check almost every three months. In this retrospective study, 331 patients (56.7% male, 43.3% female were treated with DL-PDT. We observed a full clearance in more than two-thirds of patients with one or two treatments. Different responses depend on the number of lesions and on their severity; for patients with 1–3 lesions and with grade I or II AK, a full clearance was reached in 85% of cases with a maximum of two treatments. DL-PDT in general improved skin tone and erased sun damage. Evaluating each Antera 3D images, hemoglobin concentration and pigmentation, a skin color and tone improvement in 310 patients was observed. DL-PDT appears as a promising, effective, simple, tolerable and practical treatment for actinic damage associated with AK, and even treatment of large areas can be with little or no pain. The 3D imaging allowed for quantifying in real time the aesthetic benefits

  20. TH-C-19A-05: Evaluation of a New Reusable 3D Dosimeter

    Juang, T [Medical Physics Graduate Program, Duke University Medical Center, Durham, NC (United States); Adamovics, J [Rider University, Skillman, NJ (United States); Oldham, M [Duke University Medical Center, Durham, NC (United States)

    2014-06-15

    Purpose: PRESAGE is a radiochromic plastic which has demonstrated strong potential for high resolution single-use 3D dosimetry. This study evaluates a new PRESAGE formulation (Presage-RU) in which the radiochromic response is reversible (the dosimeter optically clears after irradiation), enabling the potential for reusability. Methods: Presage-RU dose response and optical-clearing rates were evaluated in both small volume dosimeters (1×1×4.5cm) and a larger cylindrical dosimeter (8cm diameter, 4.5cm length). All dosimeters were allowed to fully optically clear in dark, room temperature conditions between irradiations. Dose response was determined by irradiating small volume samples from 0–8.0Gy and measuring change in optical density. The cylindrical dosimeter was irradiated with a simple 4-field box plan (parallel opposed pairs of 4cm×4cm AP-PA beams and 2cm×4cm lateral beams) to 20Gy. High resolution 3D dosimetry was achieved utilizing optical-CT readout. Readings were tracked up to 14 days to characterize optical clearing. Results: Initial irradiation yielded a response of 0.0119△OD/(Gy*cm) while two subsequent reirradiations yielded a lower but consistent response of 0.0087△OD/(Gy*cm). Strong linearity of dose response was observed for all irradiations. In the large cylindrical dosimeter, the integral dose within the high dose region exhibited an exponential decay in signal over time (halflife= 23.9 hours), with the dosimeter effectively cleared (0.04% of the initial signal) after 10 days. Subsequent irradiation resulted in 19.5% lower initial signal but demonstrated that the exponential clearing rate remained consistent. Results of additional subsequent irradiations will also be presented. Conclusion: This work introduces a new re-usable radiochromic dosimeter (Presage-RU) compatible with high resolution (sub-millimeter) 3D dosimetry. Sensitivity of the initial radiation was observed to be slightly higher than subsequent irradiations, but the

  1. Design and Performance Evaluation on Ultra-Wideband Time-Of-Arrival 3D Tracking System

    Ni, Jianjun; Arndt, Dickey; Ngo, Phong; Dusl, John

    2012-01-01

    A three-dimensional (3D) Ultra-Wideband (UWB) Time--of-Arrival (TOA) tracking system has been studied at NASA Johnson Space Center (JSC) to provide the tracking capability inside the International Space Station (ISS) modules for various applications. One of applications is to locate and report the location where crew experienced possible high level of carbon-dioxide and felt upset. In order to accurately locate those places in a multipath intensive environment like ISS modules, it requires a robust real-time location system (RTLS) which can provide the required accuracy and update rate. A 3D UWB TOA tracking system with two-way ranging has been proposed and studied. The designed system will be tested in the Wireless Habitat Testbed which simulates the ISS module environment. In this presentation, we discuss the 3D TOA tracking algorithm and the performance evaluation based on different tracking baseline configurations. The simulation results show that two configurations of the tracking baseline are feasible. With 100 picoseconds standard deviation (STD) of TOA estimates, the average tracking error 0.2392 feet (about 7 centimeters) can be achieved for configuration Twisted Rectangle while the average tracking error 0.9183 feet (about 28 centimeters) can be achieved for configuration Slightly-Twisted Top Rectangle . The tracking accuracy can be further improved with the improvement of the STD of TOA estimates. With 10 picoseconds STD of TOA estimates, the average tracking error 0.0239 feet (less than 1 centimeter) can be achieved for configuration "Twisted Rectangle".

  2. Evaluation of feature-based 3-d registration of probabilistic volumetric scenes

    Restrepo, Maria I.; Ulusoy, Ali O.; Mundy, Joseph L.

    2014-12-01

    Automatic estimation of the world surfaces from aerial images has seen much attention and progress in recent years. Among current modeling technologies, probabilistic volumetric models (PVMs) have evolved as an alternative representation that can learn geometry and appearance in a dense and probabilistic manner. Recent progress, in terms of storage and speed, achieved in the area of volumetric modeling, opens the opportunity to develop new frameworks that make use of the PVM to pursue the ultimate goal of creating an entire map of the earth, where one can reason about the semantics and dynamics of the 3-d world. Aligning 3-d models collected at different time-instances constitutes an important step for successful fusion of large spatio-temporal information. This paper evaluates how effectively probabilistic volumetric models can be aligned using robust feature-matching techniques, while considering different scenarios that reflect the kind of variability observed across aerial video collections from different time instances. More precisely, this work investigates variability in terms of discretization, resolution and sampling density, errors in the camera orientation, and changes in illumination and geographic characteristics. All results are given for large-scale, outdoor sites. In order to facilitate the comparison of the registration performance of PVMs to that of other 3-d reconstruction techniques, the registration pipeline is also carried out using Patch-based Multi-View Stereo (PMVS) algorithm. Registration performance is similar for scenes that have favorable geometry and the appearance characteristics necessary for high quality reconstruction. In scenes containing trees, such as a park, or many buildings, such as a city center, registration performance is significantly more accurate when using the PVM.

  3. 3D modeling and simulation of the thermal performance of solid cyclotron targets

    Avila-Rodriguez, M.A.; Sader, J.A.; McQuarrie, S.A. [Alberta Univ., Edmonton PET Centre, Cross Cancer Institute, AB (Canada); McQuarrie, S.A. [Alberta Univ., Faculty of Medicine and Dentistry, Div. of Oncologic Imaging, Edmonton, AB (Canada)

    2007-07-01

    COMSOL Multiphysics was used to model and simulate the thermal performance of solid targets irradiated with charged particles. Parametric solutions for beam power densities in the range from 1.5 10{sup 5} to 1.5 10{sup 6} W/m{sup 2} and cooling water flow velocities from 0.2 to 4.0 m/s were obtained for different plate materials. Results showed that materials with a high thermal conductivity to heat capacity ratio behave better in cooling dynamic systems requiring fast dissipation of heat. Results also showed that water flow rates greater than 2.6 L/min do not noticeably improve the heat dissipation of solid targets irradiated with charged particles. (authors)

  4. A 3-D thermal regime model suitable for cold accumulation zones of polythermal mountain glaciers

    Gilbert, A.; Gagliardini, O.; Vincent, C.; Wagnon, P.

    2014-09-01

    Analysis of the thermal and mechanical response of high altitude glaciers to climate change is crucial to assess future glacier hazards associated with thermal regime changes. This paper presents a new fully thermo-mechanically coupled transient thermal regime model including enthalpy transport, firn densification, full-Stokes porous flow, free surface evolution, strain heating, surface meltwater percolation, and refreezing. The model is forced by daily air temperature data and can therefore be used to perform prognostic simulations for different future climate scenarios. The set of equations is solved using the finite element ice sheet/ice flow model Elmer/Ice. This model is applied to the Col du Dôme glacier (Mont Blanc area, 4250 m a.s.l., France) where a comprehensive data set is available. The results show that the model is capable of reproducing observed density and velocity fields as well as borehole temperature evolution. The strong spatial variability of englacial temperature change observed at Col du Dôme is well reproduced. This spatial variability is mainly a result of the variability of the slope aspect of the glacier surface and snow accumulation. Results support the use of this model to study the influence of climate change on cold accumulation zones, in particular to estimate where and under what conditions glaciers will become temperate in the future.

  5. A Numerical Study on the Thermal Conductivity of 3D Woven C/C Composites at High Temperature

    Shigang, Ai; Rujie, He; Yongmao, Pei

    2015-12-01

    Experimental data for Carbon/Carbon (C/C) constituent materials are combined with a three dimensional steady state heat transfer finite element analysis to demonstrate the average in-plane and out-of-plane thermal conductivities (TCs) of C/C composites. The finite element analysis is carried out at two distinct length scales: (a) a micro scale comparable with the diameter of carbon fibres and (b) a meso scale comparable with the carbon fibre yarns. Micro-scale model calculate the TCs at the fibre yarn scale in the three orthogonal directions ( x, y and z). The output results from the micro-scale model are then incorporated in the meso-scale model to obtain the global TCs of the 3D C/C composite. The simulation results are quite consistent with the theoretical and experimental counterparts reported in references. Based on the numerical approach, TCs of the 3D C/C composite are calculated from 300 to 2500 K. Particular attention is given in elucidating the variations of the TCs with temperature. The multi-scale models provide an efficient approach to predict the TCs of 3D textile materials, which is helpful for the thermodynamic property analysis and structure design of the C/C composites.

  6. Evaluation of failing hemodialysis fistulas with multidetector CT angiography: Comparison of different 3D planes

    Karadeli, E. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey); Tarhan, N.C. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey)], E-mail: caglat@baskent-ank.edu.tr; Ulu, E.M. Kayahan; Tutar, N.U. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey); Basaran, O. [Department of General Surgery, Baskent University, Faculty of Medicine, Ankara (Turkey); Coskun, M.; Niron, E.A. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey)

    2009-01-15

    Purpose: To evaluate failing hemodialysis fistula complications using 16-detector MDCTA, and to assess the accuracies of different 3D planes. Materials and methods: Thirty patients (16 men, 14 women, aged 27-79 years) were referred for hemodialysis access dysfunction. Thirty-one MDCTA exams were done prior to fistulography. For MDCTA, contrast was administered (2 mL/kg at 5 mL/s) via a peripheral vein in the contralateral arm. Axial MIP, coronal MIP, and VRT images were constructed. Venous complications were evaluated on axial source images, on each 3D plane, and on all-planes together. Results were analyzed using McNemar test. Results: Axial MIP, VRT and all-planes evaluations were most sensitive for fistula site detection (93%). Coronal MIP had the highest sensitivity, specificity and accuracy (35%, 96%, and 85%, respectively) for detecting venous stenosis. VRT and all-planes had the highest sensitivity and accuracy for detecting aneurysms (100%). All-planes and axial MIP were most sensitive for detecting venous occlusion (61% and 54%). Comparisons of detection frequencies for each venous pathology between the five categories of MDCTA revealed no significant differences (P > 0.05). MDCTA additionally showed 3 partially thrombosed aneurysms, 4 anastomosis site stenosis and 12 arterial complications. Conclusion: MDCTA overall gives low sensitivity for detection of central vein stenosis and moderate sensitivity for occlusion. For most pathology, all-planes evaluation of MDCTA gives highest sensitivity and accuracy rates when compared to other planes. For venous stenosis and occlusion, MDCTA should be considered when ultrasonography and fistulography are inconclusive. MDCTA is helpful in identifying aneurysms, collaterals, partial venous thromboses and additional arterial, anastomosis site pathologies.

  7. A novel time dependent gamma evaluation function for dynamic 2D and 3D dose distributions.

    Podesta, Mark; Persoon, Lucas C G G; Verhaegen, Frank

    2014-10-21

    Modern external beam radiotherapy requires detailed verification and quality assurance so that confidence can be placed on both the delivery of a single treatment fraction and on the consistency of delivery throughout the treatment course. To verify dose distributions, a comparison between prediction and measurement must be made. Comparisons between two dose distributions are commonly performed using a Gamma evaluation which is a calculation of two quantities on a pixel by pixel basis; the dose difference, and the distance to agreement. By providing acceptance criteria (e.g. 3%, 3 mm), the function will find the most appropriate match within its two degrees of freedom. For complex dynamic treatments such as IMRT or VMAT it is important to verify the dose delivery in a time dependent manner and so a gamma evaluation that includes a degree of freedom in the time domain via a third parameter, time to agreement, is presented here. A C++ (mex) based gamma function was created that could be run on either CPU and GPU computing platforms that would allow a degree of freedom in the time domain. Simple test cases were created in both 2D and 3D comprising of simple geometrical shapes with well-defined boundaries varying over time. Changes of varying magnitude in either space or time were introduced and repeated gamma analyses were performed varying the criteria. A clinical VMAT case was also included, artificial air bubbles of varying size were introduced to a patient geometry, along with shifts of varying magnitude in treatment time. For all test cases where errors in distance, dose or time were introduced, the time dependent gamma evaluation could accurately highlight the errors.The time dependent gamma function presented here allows time to be included as a degree of freedom in gamma evaluations. The function allows for 2D and 3D data sets which are varying over time to be compared using appropriate criteria without penalising minor offsets of subsequent radiation fields

  8. Can 3D ultrasound identify trochlea dysplasia in newborns? Evaluation and applicability of a technique

    Kohlhof, Hendrik, E-mail: Hendrik.Kohlhof@ukb.uni-bonn.de [Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn (Germany); Heidt, Christoph, E-mail: Christoph.heidt@kispi.uzh.ch [Department of Orthopedic Surgery, University Children' s Hospital Zurich, Steinwiesstrasse 74, 8032 Switzerland (Switzerland); Bähler, Alexandrine, E-mail: Alexandrine.baehler@insel.ch [Department of Pediatric Radiology, University Children' s Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland); Kohl, Sandro, E-mail: sandro.kohl@insel.ch [Department of Orthopedic Surgery, University Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland); Gravius, Sascha, E-mail: sascha.gravius@ukb.uni-bonn.de [Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn (Germany); Friedrich, Max J., E-mail: Max.Friedrich@ukb.uni-bonn.de [Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn (Germany); Ziebarth, Kai, E-mail: kai.ziebarth@insel.ch [Department of Orthopedic Surgery, University Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland); Stranzinger, Enno, E-mail: Enno.Stranzinger@insel.ch [Department of Pediatric Radiology, University Children' s Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland)

    2015-06-15

    Highlights: • We evaluated a possible screening method for trochlea dysplasia. • 3D ultrasound was used to perform the measurements on standardized axial planes. • The evaluation of the technique showed comparable results to other studies. • This technique may be used as a screening technique as it is quick and easy to perform. - Abstract: Femoro-patellar dysplasia is considered as a significant risk factor of patellar instability. Different studies suggest that the shape of the trochlea is already developed in early childhood. Therefore early identification of a dysplastic configuration might be relevant information for the treating physician. An easy applicable routine screening of the trochlea is yet not available. The purpose of this study was to establish and evaluate a screening method for femoro-patellar dysplasia using 3D ultrasound. From 2012 to 2013 we prospectively imaged 160 consecutive femoro-patellar joints in 80 newborns from the 36th to 61st gestational week that underwent a routine hip sonography (Graf). All ultrasounds were performed by a pediatric radiologist with only minimal additional time to the routine hip ultrasound. In 30° flexion of the knee, axial, coronal, and sagittal reformats were used to standardize a reconstructed axial plane through the femoral condyle and the mid-patella. The sulcus angle, the lateral-to-medial facet ratio of the trochlea and the shape of the patella (Wiberg Classification) were evaluated. In all examinations reconstruction of the standardized axial plane was achieved, the mean trochlea angle was 149.1° (SD 4.9°), the lateral-to-medial facet ratio of the trochlea ratio was 1.3 (SD 0.22), and a Wiberg type I patella was found in 95% of the newborn. No statistical difference was detected between boys and girls. Using standardized reconstructions of the axial plane allows measurements to be made with lower operator dependency and higher accuracy in a short time. Therefore 3D ultrasound is an easy

  9. Evaluation of 3D printing and its potential impact on biotechnology and the chemical sciences.

    Gross, Bethany C; Erkal, Jayda L; Lockwood, Sarah Y; Chen, Chengpeng; Spence, Dana M

    2014-04-01

    Nearing 30 years since its introduction, 3D printing technology is set to revolutionize research and teaching laboratories. This feature encompasses the history of 3D printing, reviews various printing methods, and presents current applications. The authors offer an appraisal of the future direction and impact this technology will have on laboratory settings as 3D printers become more accessible.

  10. Stereoscopic uncooled thermal imaging with autostereoscopic 3D flat-screen display in military driving enhancement systems

    Haan, H.; Münzberg, M.; Schwarzkopf, U.; de la Barré, R.; Jurk, S.; Duckstein, B.

    2012-06-01

    Thermal cameras are widely used in driver vision enhancement systems. However, in pathless terrain, driving becomes challenging without having a stereoscopic perception. Stereoscopic imaging is a well-known technique already for a long time with understood physical and physiological parameters. Recently, a commercial hype has been observed, especially in display techniques. The commercial market is already flooded with systems based on goggle-aided 3D-viewing techniques. However, their use is limited for military applications since goggles are not accepted by military users for several reasons. The proposed uncooled thermal imaging stereoscopic camera with a geometrical resolution of 640x480 pixel perfectly fits to the autostereoscopic display with a 1280x768 pixels. An eye tracker detects the position of the observer's eyes and computes the pixel positions for the left and the right eye. The pixels of the flat panel are located directly behind a slanted lenticular screen and the computed thermal images are projected into the left and the right eye of the observer. This allows a stereoscopic perception of the thermal image without any viewing aids. The complete system including camera and display is ruggedized. The paper discusses the interface and performance requirements for the thermal imager as well as for the display.

  11. A Novel Methodology for Thermal Aware Silicon Area Estimation for 2D & 3D MPSoCs

    Vinod Pangracious

    2012-01-01

    Full Text Available In a multiprocessor system on chip (MPSoC IC the processor is one of the highest heat dissipating devices. The temperature generated in an IC may vary with floor plan of the chip. This paper proposes an integration and thermal analysis methodology to extract the peak temperature and temperature distribution of 2-dimensional and 3-dimensional multiprocessor system-on-chip. As we know the peak temperature of chip increases in 3-dimensional structures compared to 2-dimensional ones due to the reduced space in intra-layer and inter-layer components. In sub-nanometre scale technologies, it is inevitable to analysis the heat developed in individual chip to extract the temperature distribution of the entire chip. With thetechnology scaling in new generation ICs more and more components are integrated to a smaller area. Along with the other parameters threshold voltage is also scaled down which results in exponential increase in leakage current. This has resulted in rise in hotspot temperature value due to increase inleakage power. In this paper, we have analysed the temperature developed in an IC with four identical processors at 2.4 GHz in different floorplans. The analysis has been done for both 2D and 3D arrangements. In the 3D arrangement, a three layered structure has been considered with two Silicon layers and a thermal interface material (TIM in between them. Based on experimental results the paperproposes a methodology to reduce the peak temperature developed in 2D and 3D integrated circuits .

  12. Full 3-D numerical modeling of borehole electric image logging and the evaluation model of fracture

    2008-01-01

    A full 3-D finite element method numerical modeling program is written based on the principle and technical specification of borehole electric image well logging tool. The response of well logging is computed in the formation media model with a single fracture. The effect of changing fracture aperture and resistivity ratio to the logging response is discussed. The identification ability for two parallel fractures is also present. A quantitative evaluation formula of fracture aperture from borehole electric image logging data is set up. A case study of the model well is done to verify the accuracy of the for-mula. The result indicates that the formula is more accurate than the foreign one.

  13. Evaluation of Full Reynolds Stress Turbulence Models in FUN3D

    Dudek, Julianne C.; Carlson, Jan-Renee

    2017-01-01

    Full seven-equation Reynolds stress turbulence models are promising tools for today’s aerospace technology challenges. This paper examines two such models for computing challenging turbulent flows including shock-wave boundary layer interactions, separation and mixing layers. The Wilcox and the SSG/LRR full second-moment Reynolds stress models have been implemented into the FUN3D (Fully Unstructured Navier-Stokes Three Dimensional) unstructured Navier-Stokes code and were evaluated for four problems: a transonic two-dimensional diffuser, a supersonic axisymmetric compression corner, a compressible planar shear layer, and a subsonic axisymmetric jet. Simulation results are compared with experimental data and results computed using the more commonly used Spalart-Allmaras (SA) one-equation and the Menter Shear Stress Transport (SST-V) two-equation turbulence models.

  14. Comparative evaluation of scatter correction techniques in 3D positron emission tomography

    Zaidi, H

    2000-01-01

    Much research and development has been concentrated on the scatter compensation required for quantitative 3D PET. Increasingly sophisticated scatter correction procedures are under investigation, particularly those based on accurate scatter models, and iterative reconstruction-based scatter compensation approaches. The main difference among the correction methods is the way in which the scatter component in the selected energy window is estimated. Monte Carlo methods give further insight and might in themselves offer a possible correction procedure. Methods: Five scatter correction methods are compared in this paper where applicable. The dual-energy window (DEW) technique, the convolution-subtraction (CVS) method, two variants of the Monte Carlo-based scatter correction technique (MCBSC1 and MCBSC2) and our newly developed statistical reconstruction-based scatter correction (SRBSC) method. These scatter correction techniques are evaluated using Monte Carlo simulation studies, experimental phantom measurements...

  15. Evaluation of single photon and Geiger mode Lidar for the 3D Elevation Program

    Stoker, Jason M.; Abdullah, Qassim; Nayegandhi, Amar; Winehouse, Jayna

    2016-01-01

    Data acquired by Harris Corporation’s (Melbourne, FL, USA) Geiger-mode IntelliEarth™ sensor and Sigma Space Corporation’s (Lanham-Seabrook, MD, USA) Single Photon HRQLS sensor were evaluated and compared to accepted 3D Elevation Program (3DEP) data and survey ground control to assess the suitability of these new technologies for the 3DEP. While not able to collect data currently to meet USGS lidar base specification, this is partially due to the fact that the specification was written for linear-mode systems specifically. With little effort on part of the manufacturers of the new lidar systems and the USGS Lidar specifications team, data from these systems could soon serve the 3DEP program and its users. Many of the shortcomings noted in this study have been reported to have been corrected or improved upon in the next generation sensors.

  16. Fabrication of 3D Microfluidic Devices by Thermal Bonding of Thin Poly(methyl methacrylate) Films

    Perez, Paul

    2012-07-01

    The use of thin-film techniques for the fabrication of microfluidic devices has gained attention over the last decade, particularly for three-dimensional channel structures. The reasons for this include effective use of chip volume, mechanical flexibility, dead volume reduction, enhanced design capabilities, integration of passive elements, and scalability. Several fabrication techniques have been adapted for use on thin films: laser ablation and hot embossing are popular for channel fabrication, and lamination is widely used for channel enclosure. However, none of the previous studies have been able to achieve a strong bond that is reliable under moderate positive pressures. The present work aims to develop a thin-film process that provides design versatility, speed, channel profile homogeneity, and the reliability that others fail to achieve. The three building blocks of the proposed baseline were fifty-micron poly(methyl methacrylate) thin films as substrates, channel patterning by laser ablation, and device assembly by thermal-fusion bonding. Channel fabrication was characterized and tuned to produce the desired dimensions and surface roughness. Thermal bonding was performed using an adapted mechanical testing device and optimized to produce the maximum bonding strength without significant channel deformation. Bonding multilayered devices, incorporating conduction lines, and integrating various types of membranes as passive elements demonstrated the versatility of the process. Finally, this baseline was used to fabricate a droplet generator and a DNA detection chip based on micro-bead agglomeration. It was found that a combination of low laser power and scanning speed produced channel surfaces with better uniformity than those obtained with higher values. In addition, the implemented bonding technique provided the process with the most reliable bond strength reported, so far, for thin-film microfluidics. Overall, the present work proved to be versatile

  17. Evaluation of helper-dependent canine adenovirus vectors in a 3D human CNS model

    Simão, Daniel; Pinto, Catarina; Fernandes, Paulo; Peddie, Christopher J.; Piersanti, Stefania; Collinson, Lucy M.; Salinas, Sara; Saggio, Isabella; Schiavo, Giampietro; Kremer, Eric J.; Brito, Catarina; Alves, Paula M.

    2017-01-01

    Gene therapy is a promising approach with enormous potential for treatment of neurodegenerative disorders. Viral vectors derived from canine adenovirus type 2 (CAV-2) present attractive features for gene delivery strategies in the human brain, by preferentially transducing neurons, are capable of efficient axonal transport to afferent brain structures, have a 30-kb cloning capacity and have low innate and induced immunogenicity in pre-clinical tests. For clinical translation, in-depth pre-clinical evaluation of efficacy and safety in a human setting is primordial. Stem cell-derived human neural cells have a great potential as complementary tools by bridging the gap between animal models, which often diverge considerably from human phenotype, and clinical trials. Herein, we explore helper-dependent CAV-2 (hd-CAV-2) efficacy and safety for gene delivery in a human stem cell-derived 3D neural in vitro model. Assessment of hd-CAV-2 vector efficacy was performed at different multiplicities of infection, by evaluating transgene expression and impact on cell viability, ultrastructural cellular organization and neuronal gene expression. Under optimized conditions, hd-CAV-2 transduction led to stable long-term transgene expression with minimal toxicity. hd-CAV-2 preferentially transduced neurons, while human adenovirus type 5 (HAdV5) showed increased tropism towards glial cells. This work demonstrates, in a physiologically relevant 3D model, that hd-CAV-2 vectors are efficient tools for gene delivery to human neurons, with stable long-term transgene expression and minimal cytotoxicity. PMID:26181626

  18. CAVAREV-an open platform for evaluating 3D and 4D cardiac vasculature reconstruction

    Rohkohl, Christopher; Hornegger, Joachim [Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander University Erlangen-Nuremberg, Martensstr. 3, 91058 Erlangen (Germany); Lauritsch, Guenter [Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany); Keil, Andreas, E-mail: christopher.rohkohl@informatik.uni-erlangen.d, E-mail: guenter.lauritsch@siemens.co, E-mail: andreas.keil@cs.tum.ed, E-mail: joachim.hornegger@informatik.uni-erlangen.d [Computer Aided Medical Procedures and Augmented Reality, TU Muenchen, Boltzmannstr. 3, 85748 Garching (Germany)

    2010-05-21

    The 3D reconstruction of cardiac vasculature, e.g. the coronary arteries, using C-arm CT (rotational angiography) is an active and challenging field of research. There are numerous publications on different reconstruction techniques. However, there is still a lack of comparability of achieved results for several reasons: foremost, datasets used in publications are not open to public and thus experiments are not reproducible by other researchers. Further, the results highly depend on the vasculature motion, i.e. cardiac and breathing motion patterns which are also not comparable across publications. We aim to close this gap by providing an open platform, called Cavarev (CArdiac VAsculature Reconstruction EValuation). It features two simulated dynamic projection datasets based on the 4D XCAT phantom with contrasted coronary arteries which was derived from patient data. In the first dataset, the vasculature undergoes a continuous periodic motion. The second dataset contains aperiodic heart motion by including additional breathing motion. The geometry calibration and acquisition protocol were obtained from a real-world C-arm system. For qualitative evaluation of the reconstruction results, the correlation of the morphology is used. Two segmentation-based quality measures are introduced which allow us to assess the 3D and 4D reconstruction quality. They are based on the spatial overlap of the vasculature reconstruction with the ground truth. The measures enable a comprehensive analysis and comparison of reconstruction results independent from the utilized reconstruction algorithm. An online platform (www.cavarev.com) is provided where the datasets can be downloaded, researchers can manage and publish algorithm results and download a reference C++ and Matlab implementation.

  19. 3D analysis of thermal and stress evolution during laser cladding of bioactive glass coatings.

    Krzyzanowski, Michal; Bajda, Szymon; Liu, Yijun; Triantaphyllou, Andrew; Mark Rainforth, W; Glendenning, Malcolm

    2016-06-01

    Thermal and strain-stress transient fields during laser cladding of bioactive glass coatings on the Ti6Al4V alloy basement were numerically calculated and analysed. Conditions leading to micro-cracking susceptibility of the coating have been investigated using the finite element based modelling supported by experimental results of microscopic investigation of the sample coatings. Consecutive temperature and stress peaks are developed within the cladded material as a result of the laser beam moving along the complex trajectory, which can lead to micro-cracking. The preheated to 500°C base plate allowed for decrease of the laser power and lowering of the cooling speed between the consecutive temperature peaks contributing in such way to achievement of lower cracking susceptibility. The cooling rate during cladding of the second and the third layer was lower than during cladding of the first one, in such way, contributing towards improvement of cracking resistance of the subsequent layers due to progressive accumulation of heat over the process.

  20. A 3-D mathematical model to identify organ-specific risks in rats during thermal stress.

    Rakesh, Vineet; Stallings, Jonathan D; Helwig, Bryan G; Leon, Lisa R; Jackson, David A; Reifman, Jaques

    2013-12-01

    Early prediction of the adverse outcomes associated with heat stress is critical for effective management and mitigation of injury, which may sometimes lead to extreme undesirable clinical conditions, such as multiorgan dysfunction syndrome and death. Here, we developed a computational model to predict the spatiotemporal temperature distribution in a rat exposed to heat stress in an attempt to understand the correlation between heat load and differential organ dysfunction. The model includes a three-dimensional representation of the rat anatomy obtained from medical imaging and incorporates the key mechanisms of heat transfer during thermoregulation. We formulated a novel approach to estimate blood temperature by accounting for blood mixing from the different organs and to estimate the effects of the circadian rhythm in body temperature by considering day-night variations in metabolic heat generation and blood perfusion. We validated the model using in vivo core temperature measurements in control and heat-stressed rats and other published experimental data. The model predictions were within 1 SD of the measured data. The liver demonstrated the greatest susceptibility to heat stress, with the maximum temperature reaching 2°C higher than the measured core temperature and 95% of its volume exceeding the targeted experimental core temperature. Other organs also attained temperatures greater than the core temperature, illustrating the need to monitor multiple organs during heat stress. The model facilitates the identification of organ-specific risks during heat stress and has the potential to aid in the development of improved clinical strategies for thermal-injury prevention and management.

  1. CCTV Coverage Index Based on Surveillance Resolution and Its Evaluation Using 3D Spatial Analysis

    Kyoungah Choi

    2015-09-01

    Full Text Available We propose a novel approach to evaluating how effectively a closed circuit television (CCTV system can monitor a targeted area. With 3D models of the target area and the camera parameters of the CCTV system, the approach produces surveillance coverage index, which is newly defined in this study as a quantitative measure for surveillance performance. This index indicates the proportion of the space being monitored with a sufficient resolution to the entire space of the target area. It is determined by computing surveillance resolution at every position and orientation, which indicates how closely a specific object can be monitored with a CCTV system. We present full mathematical derivation for the resolution, which depends on the location and orientation of the object as well as the geometric model of a camera. With the proposed approach, we quantitatively evaluated the surveillance coverage of a CCTV system in an underground parking area. Our evaluation process provided various quantitative-analysis results, compelling us to examine the design of the CCTV system prior to its installation and understand the surveillance capability of an existing CCTV system.

  2. Evaluating the accuracy of orthophotos and 3D models from UAV photogrammetry

    Julge, Kalev; Ellmann, Artu

    2015-04-01

    Rapid development of unmanned aerial vehicles (UAV) in recent years has made their use for various applications more feasible. This contribution evaluates the accuracy and quality of different UAV remote sensing products (i.e. orthorectified image, point cloud and 3D model). Two different autonomous fixed wing UAV systems were used to collect the aerial photographs. One is a mass-produced commercial UAV system, the other is a similar state-of-the-art UAV system. Three different study areas with varying sizes and characteristics (including urban areas, forests, fields, etc.) were surveyed. The UAV point clouds, 3D models and orthophotos were generated with three different commercial and free-ware software. The performance of each of these was evaluated. The effect of flying height on the accuracy of the results was explored, as well as the optimum number and placement of ground control points. Also the achieved results, when the only georeferencing data originates from the UAV system's on-board GNSS and inertial measurement unit, are investigated. Problems regarding the alignment of certain types of aerial photos (e.g. captured over forested areas) are discussed. The quality and accuracy of UAV photogrammetry products are evaluated by comparing them with control measurements made with GNSS-measurements on the ground, as well as high-resolution airborne laser scanning data and other available orthophotos (e.g. those acquired for large scale national mapping). Vertical comparisons are made on surfaces that have remained unchanged in all campaigns, e.g. paved roads. Planar comparisons are performed by control surveys of objects that are clearly identifiable on orthophotos. The statistics of these differences are used to evaluate the accuracy of UAV remote sensing. Some recommendations are given on how to conduct UAV mapping campaigns cost-effectively and with minimal time-consumption while still ensuring the quality and accuracy of the UAV data products. Also the

  3. Comparative evaluation between the Vitapan Classical and 3D-Master color scales

    Rubens da Rocha Portal Junior

    2008-01-01

    Full Text Available Objective: To evaluate the use of two scales as regard efficiency of color selection and the selection technique used by dental surgeons that practice in the municipality of Belém in the State of Pará, and last year Dentistry students at the Centro Universitário do Pará – Brazil. Method: Four healthy maxillary anterior teeth were chosen in two volunteers. The teeth were submitted to color selection by threeprofessionals experienced in dental prosthesis. Among the interviewees, there were 30 were professionals and 15 academics, and the scales analyzed were Vitapan Classical and Vitapan 3D-Master. A questionnaire containing seven questions on the color selectiontechnique was applied, in which the following factors were analyzed: room, light source, ideal time, and whether the teeth were humid,as well as other requirements for correct color selection. The data obtained were submitted to the Mann-Whitney nonparametric test (5% as it concerned an independent variable and subjective data. Results: The results showed that there were no statistically significant differences between the scales researched when color selection wasmade with an unsuitable technique and that dental surgeons and academics need to improve their color selection technique. Conclusion: It was concluded that there is no difference between the use of the Vitapan Classical and Vitapan 3D-Master scales when thetechnique used does not follow ideal selection patterns, the number of errors being statistically higher than the number of correct choices, indicating a need for technical improvement in color selection by dental surgeons and academics.

  4. LBP and lower limb discrepancy: 3D evaluation of postural rebalancing via underfoot wedge correction.

    D'Amico, Moreno; Roncoletta, Piero; Di Felice, Francesca; Porto, Daniele; Bellomo, Rosagrazia; Saggini, Raoul

    2012-01-01

    Leg Length Discrepancy (LLD) is very often associated to Low Back Pain (LBP), but still controversial is the use of underfoot wedge correction (heel rise) to re-balance pelvis and trunk posture. In a review of our last 5 years clinical activity we observed that more than 70% out of 300 LBP patients presented a LLD. In more than 80 % we ascertained, via Baropodography, the presence of underfoot asymmetric load, during standing. More durable therapy recovery effect has been observed when LLD correction had been adopted. These reasons led us to start a study to assess if a Full 3D multifactorial Posture evaluation approach, by means of Opto-electronic device associated to foot pressure maps recording, was able to quantitatively discriminate the clinically observed phenomena. On a 94 LBP (av. age 46.3±16 Y range 15-82 Y) patients sample, 83 (88%) have been found to improve posture when LLD was corrected. The 94 patients showed a mean lower limb discrepancy of μ=8±3.2mm associated to a mean scoliotic lumbar curve μ=10.5°±5.1° Cobb (frontal plane), mean Spinal offset μ=6.6±4.9mm and mean Global offset 10.7±8.8mm. The applied paired t-test comparison (indifferent vs. corrected orthostasis) showed significant (p < 0.05) postural improvements could be obtained in the whole or in a part of the considered parameters, both in rebalancing and in spine deformities reduction after the application of suitable under-foot wedge. The joint 3D opto-electronic and foot pressure map approach proved to be effective to control several clinical parameters with statistical significance.

  5. Evaluation of a Gait Assessment Module Using 3D Motion Capture Technology

    Baskwill, Amanda J.; Belli, Patricia; Kelleher, Leila

    2017-01-01

    Background Gait analysis is the study of human locomotion. In massage therapy, this observation is part of an assessment process that informs treatment planning. Massage therapy students must apply the theory of gait assessment to simulated patients. At Humber College, the gait assessment module traditionally consists of a textbook reading and a three-hour, in-class session in which students perform gait assessment on each other. In 2015, Humber College acquired a three-dimensional motion capture system. Purpose The purpose was to evaluate the use of 3D motion capture in a gait assessment module compared to the traditional gait assessment module. Participants Semester 2 massage therapy students who were enrolled in Massage Theory 2 (n = 38). Research Design Quasi-experimental, wait-list comparison study. Intervention The intervention group participated in an in-class session with a Qualisys motion capture system. Main Outcome Measure(s) The outcomes included knowledge and application of gait assessment theory as measured by quizzes, and students’ satisfaction as measured through a questionnaire. Results There were no statistically significant differences in baseline and post-module knowledge between both groups (pre-module: p = .46; post-module: p = .63). There was also no difference between groups on the final application question (p = .13). The intervention group enjoyed the in-class session because they could visualize the content, whereas the comparison group enjoyed the interactivity of the session. The intervention group recommended adding the assessment of gait on their classmates to their experience. Both groups noted more time was needed for the gait assessment module. Conclusions Based on the results of this study, it is recommended that the gait assessment module combine both the traditional in-class session and the 3D motion capture system. PMID:28293329

  6. 3D RECONSTRUCTION FROM MULTI-VIEW MEDICAL X-RAY IMAGES – REVIEW AND EVALUATION OF EXISTING METHODS

    S. Hosseinian

    2015-12-01

    Full Text Available The 3D concept is extremely important in clinical studies of human body. Accurate 3D models of bony structures are currently required in clinical routine for diagnosis, patient follow-up, surgical planning, computer assisted surgery and biomechanical applications. However, 3D conventional medical imaging techniques such as computed tomography (CT scan and magnetic resonance imaging (MRI have serious limitations such as using in non-weight-bearing positions, costs and high radiation dose(for CT. Therefore, 3D reconstruction methods from biplanar X-ray images have been taken into consideration as reliable alternative methods in order to achieve accurate 3D models with low dose radiation in weight-bearing positions. Different methods have been offered for 3D reconstruction from X-ray images using photogrammetry which should be assessed. In this paper, after demonstrating the principles of 3D reconstruction from X-ray images, different existing methods of 3D reconstruction of bony structures from radiographs are classified and evaluated with various metrics and their advantages and disadvantages are mentioned. Finally, a comparison has been done on the presented methods with respect to several metrics such as accuracy, reconstruction time and their applications. With regards to the research, each method has several advantages and disadvantages which should be considered for a specific application.

  7. Ultrasound and 3D Skin Imaging: Methods to Evaluate Efficacy of Striae Distensae Treatment

    Mariella Bleve

    2012-01-01

    Full Text Available Background. Over time, the striae rubra develop into striae alba that appear white, flat, and depressed. It is very important to determine the optimum striae management. In order to evaluate the effectiveness of these therapies, objective measurement tools are necessary. Objective. The aim of this study is to evaluate if ultrasonography and PRIMOS can be used to obtain an objective assessment of stretch marks type and stage; furthermore, we aim to apply these techniques to evaluate the efficacy of a topical treatment. Methods. 20 volunteers were enrolled with a two-month study. A marketed cosmetic product was used as the active over one body area. The controlateral area with stretch marks was treated with a “placebo” formulation without active, as a control. The instrumental evaluation was carried out at the beginning of the trial (baseline values or 0, after 1 month (1, and at the end of the study (2. Results. PRIMOS was able to measure and document striae distensae maturation; furthermore, ultrasound imaging permitted to visualize and diagnose the striae. Statistical analysis of skin roughness demonstrated a statistically significant reduction of Rp value only in a treated group. In fact, the Rp value represented a maximum peak height in the area selected. These results demonstrated that after two months of treatment only the striae rubra can be treated successfully. Conclusions. This work demonstrated that the 22MHz ultrasound can diagnose stretch marks; PRIMOS device can detect and measure striae distensae type and maturation. Furthermore, the high-frequency ultrasound and the 3D image device, described in this work, can be successfully employed in order to evaluate the efficacy of a topical treatment.

  8. A 3D-printed polymer micro-gripper with self-defined electrical tracks and thermal actuator

    Alblalaihid, Khalid; Overton, James; Lawes, Simon; Kinnell, Peter

    2017-04-01

    This paper presents a simple fabrication process that allows for isolated metal tracks to be easily defined on the surface of 3D printed micro-scale polymer components. The process makes use of a standard low cost conformal sputter coating system to quickly deposit thin film metal layers on to the surface of 3D printed polymer micro parts. The key novelty lies in the inclusion of inbuilt masking features, on the surface of the polymer parts, to ensure that the conformal metal layer can be effectively broken to create electrically isolated metal features. The presented process is extremely flexible, and it is envisaged that it may be applied to a wide range of sensor and actuator applications. To demonstrate the process a polymer micro-scale gripper with an inbuilt thermal actuator is designed and fabricated. In this work the design methodology for creating the micro-gripper is presented, illustrating how the rapid and flexible manufacturing process allows for fast cycle time design iterations to be performed. In addition the compatibility of this approach with traditional design and analysis techniques such as basic finite element simulation is also demonstrated with simulation results in reasonable agreement with experimental performance data for the micro-gripper.

  9. Efficacy of 3-D computed tomographic reconstruction in evaluating anatomical relationships of colovesical fistula.

    Shinojima, Toshiaki; Nakajima, Fumio; Koizumi, Jun

    2002-04-01

    A case of colovesical fistula is reported. The anatomy of the pelvis was determined preoperatively with 3-D computed tomography (CT), and the fistula, including adjacent structures, could clearly be seen. Compared with conventional axial CT imaging, 3-D CT provided better and more complete visualization of the anatomical relationships, which facilitated the surgical procedure and provided a good outcome.

  10. 3D-CT evaluation of secondary alveolar bone grafts in alveolar clefts

    Naitoh, Hiroshi; Nishimura, Yoshihiko [Kyoto Univ. (Japan). Graduate School of Medicine; Yamawaki, Yoshiroh [Kyoto Katsura Hospital (Japan); Morimoto, Naoki [Kobe City General Hospital (Japan)

    2002-07-01

    From 1994 to 2000, we treated 116 patients with cleft alveolus by secondary alveolar bone grafts, and 48 of them were evaluated morphologically with 3D-CT. The frequency of successful bony bridging was significantly higher in the group whose grafts were completely enveloped (including the anterior alveolar ridge) with a mucoperiosteal flap. The frequency was also significantly higher in the group who underwent bone grafts at the age of 13 or less, and canine eruptions did not influence the ratio. Some cases showed such an improved growth pattern of grafted bone that the shape of the affected maxilla resembled that of the normal side, after long-term follow-up observations. The growth increment was remarkable in anterior maxillary height. Orthodontic management guides the canine or incisor into the reconstructed area of the previous cleft. We surmise that the new occlusal position puts pressure on the grafted bone and promotes further osteogenesis. These findings show that it is important to produce sufficient bony bridge to guide the canine or incisor, not the volume of grafted bone, in secondary alveolar bone grafts. Long-term follow-up observation, after more than 2-3 years, is also necessary to evaluate secondary alveolar bone grafts. (author)

  11. 3D FE Analysis of Thermal Behavior of Billet in Rod and Wire Hot Continuous Rolling Process

    YUAN Si-yu; ZHANG Li-wen; LIAO Shu-lun; QI Min; ZHEN Yu; GUO Shu-qi

    2007-01-01

    An FE model was developed to study thermal behavior during the rod and wire hot continuous rolling process. The FE code MSC.Marc was used in the simulation using implicit static arithmetic. The whole rolling process of 30 passes was separated and simulated with several continuous 3D elastic-plastic FE models. A rigid pushing body and a data transfer technique were introduced into this model. The on-line experiments were conducted on 304 stainless steel and GCr15 steel hot continuous rolling process to prove the results of simulation by implicit static FEM. The results show that the temperature results of finite element simulations are in good agreement with experiments, which indicate that the FE model developed in this study is effective and efficient.

  12. Wave propagation analysis of quasi-3D FG nanobeams in thermal environment based on nonlocal strain gradient theory

    Ebrahimi, Farzad; Barati, Mohammad Reza

    2016-09-01

    This article examines the application of nonlocal strain gradient elasticity theory to wave dispersion behavior of a size-dependent functionally graded (FG) nanobeam in thermal environment. The theory contains two scale parameters corresponding to both nonlocal and strain gradient effects. A quasi-3D sinusoidal beam theory considering shear and normal deformations is employed to present the formulation. Mori-Tanaka micromechanical model is used to describe functionally graded material properties. Hamilton's principle is employed to obtain the governing equations of nanobeam accounting for thickness stretching effect. These equations are solved analytically to find the wave frequencies and phase velocities of the FG nanobeam. It is indicated that wave dispersion behavior of FG nanobeams is significantly affected by temperature rise, nonlocality, length scale parameter and material composition.

  13. 3D simulation of the thermal and chemical plumes using open source software; Simulacion 3D de las plumas termica y quimica mediante software de codigo libre

    Saenz Temino, J. L.; Lerones Martin, J.; Gonzalez Delgado, J.

    2013-07-01

    The interaction of thermal and chemical plumes in the region of the Irish Sea near the site has been simulated using a finite element model representative of the local hydrodynamic regime, concluding how the method of selected cooling, open cycle, is physically and environmentally feasible. Furthermore, tunnel lengths required for each scenario under discussion have been preliminarily defined, varying in a range from 1800 to 2300 meters for a unit (1 tunnel), 4400-6300 meters of two units (2 tunnels) and 8000 meters to three units (2 tunnels), depending on the chosen technology.

  14. An Evaluation of 3D Woven Orthogonal Composites' Potential in the Automotive Supply Chain

    Taylor, Dalia

    The automotive supply chain and its management can be a very complex process and comprises a long dynamic and complex network that consists of four primary segments: original equipment manufacturers (OEMs), first tier suppliers, sub tiers suppliers, and infrastructure suppliers. During the analysis of the current automotive industry it was identified that textile industry importance is considerable increasing as a part of the global automotive supply chain, because textile products are used for interior, exterior and even suspension parts and components. Automotive industry has an increasing demand for higher quality exterior panels with better functional properties and reduced weight. One of the main potentials for this demand is based on the three-dimensional woven composites technology innovations which can replace an existing technology. The new role of the textile industry could make important changes in the automotive supply chain industry, such as: changes in the size of the supply chain, the time to the market and the position of textile industry in the automotive supply chain structure. 3D composite materials from high performance fibers, such as glass and carbon, have been used for automotive applications in a limited way due to the low production rate and the lack of research and development. This research will contribute to the understanding of textile composites in transportation and the textile parameters that affect the performance characteristics of these materials. The research examines the performance characteristics of lighter and stronger 3D woven fabric composites made from fiberglass with the aim to improve fuel efficiency by reducing the total vehicle weight while maintaining safety standards. The performance characteristics of the 3D woven fabric composite can be designed by changing different construction parameters, such as picks density, pick roving linear density, arrangements of warp and z-yarns, and the number of warp and picks layers

  15. 3D-2D registration of cerebral angiograms: a method and evaluation on clinical images.

    Mitrovic, Uroš; Špiclin, Žiga; Likar, Boštjan; Pernuš, Franjo

    2013-08-01

    Endovascular image-guided interventions (EIGI) involve navigation of a catheter through the vasculature followed by application of treatment at the site of anomaly using live 2D projection images for guidance. 3D images acquired prior to EIGI are used to quantify the vascular anomaly and plan the intervention. If fused with the information of live 2D images they can also facilitate navigation and treatment. For this purpose 3D-2D image registration is required. Although several 3D-2D registration methods for EIGI achieve registration accuracy below 1 mm, their clinical application is still limited by insufficient robustness or reliability. In this paper, we propose a 3D-2D registration method based on matching a 3D vasculature model to intensity gradients of live 2D images. To objectively validate 3D-2D registration methods, we acquired a clinical image database of 10 patients undergoing cerebral EIGI and established "gold standard" registrations by aligning fiducial markers in 3D and 2D images. The proposed method had mean registration accuracy below 0.65 mm, which was comparable to tested state-of-the-art methods, and execution time below 1 s. With the highest rate of successful registrations and the highest capture range the proposed method was the most robust and thus a good candidate for application in EIGI.

  16. Solar Thermal Concept Evaluation

    Hawk, Clark W.; Bonometti, Joseph A.

    1995-01-01

    Concentrated solar thermal energy can be utilized in a variety of high temperature applications for both terrestrial and space environments. In each application, knowledge of the collector and absorber's heat exchange interaction is required. To understand this coupled mechanism, various concentrator types and geometries, as well as, their relationship to the physical absorber mechanics were investigated. To conduct experimental tests various parts of a 5,000 watt, thermal concentrator, facility were made and evaluated. This was in anticipation at a larger NASA facility proposed for construction. Although much of the work centered on solar thermal propulsion for an upper stage (less than one pound thrust range), the information generated and the facility's capabilities are applicable to material processing, power generation and similar uses. The numerical calculations used to design the laboratory mirror and the procedure for evaluating other solar collectors are presented here. The mirror design is based on a hexagonal faceted system, which uses a spherical approximation to the parabolic surface. The work began with a few two dimensional estimates and continued with a full, three dimensional, numerical algorithm written in FORTRAN code. This was compared to a full geometry, ray trace program, BEAM 4, which optimizes the curvatures, based on purely optical considerations. Founded on numerical results, the characteristics of a faceted concentrator were construed. The numerical methodologies themselves were evaluated and categorized. As a result, the three-dimensional FORTRAN code was the method chosen to construct the mirrors, due to its overall accuracy and superior results to the ray trace program. This information is being used to fabricate and subsequently, laser map the actual mirror surfaces. Evaluation of concentrator mirrors, thermal applications and scaling the results of the 10 foot diameter mirror to a much larger concentrator, were studied. Evaluations

  17. Evaluation of Bogie Frame Safety of Shanghai Metro Line 1 by 3D FEM Analysis

    Xiongyao, Xie; Guolong, Jin; Rulu, Wang

    2010-05-01

    The vehicle bogies of Shanghai metro line 1 began to crack just in the third year after the trains operated. More than 50 cracks occurred in the succeeding six year during the train operation. This paper evaluated the safety of the motorized bogies. First, the loading conditions imposed on the vehicle structure were calculated based on the measured data in service of the train, and compared with the original design load. Then, this paper calculated simulated the stress of the vehicle bogie by 3D FEM, and presented the distribution of every stress concentration point in Goodman fatigue diagram. The computational locations of the strength less than the safety are agreed with where cracks have happened. Finally, this paper calculated the fatigue life of the motor bracket of the bogie through S-N curve based on revised Miner theory. In conclusion, this paper think that the bogie cracks of Shanghai metro line 1 are contributed by the overburden fatigue load, and ignoring the lateral vibration load in the design of the vehicle bogie is the important cause that bogie cracks occurred far earlier than in the designed time.

  18. Foot roll-over evaluation based on 3D dynamic foot scan.

    Samson, William; Van Hamme, Angèle; Sanchez, Stéphane; Chèze, Laurence; Van Sint Jan, Serge; Feipel, Véronique

    2014-01-01

    Foot roll-over is commonly analyzed to evaluate gait pathologies. The current study utilized a dynamic foot scanner (DFS) to analyze foot roll-over. The right feet of ten healthy subjects were assessed during gait trials with a DFS system integrated into a walkway. A foot sole picture was computed by vertically projecting points from the 3D foot shape which were lower than a threshold height of 15 mm. A 'height' value of these projected points was determined; corresponding to the initial vertical coordinates prior to projection. Similar to pedobarographic analysis, the foot sole picture was segmented into anatomical regions of interest (ROIs) to process mean height (average of height data by ROI) and projected surface (area of the projected foot sole by ROI). Results showed that these variables evolved differently to plantar pressure data previously reported in the literature, mainly due to the specificity of each physical quantity (millimeters vs Pascals). Compared to plantar pressure data arising from surface contact by the foot, the current method takes into account the whole plantar aspect of the foot, including the parts that do not make contact with the support surface. The current approach using height data could contribute to a better understanding of specific aspects of foot motion during walking, such as plantar arch height and the windlass mechanism. Results of this study show the underlying method is reliable. Further investigation is required to validate the DFS measurements within a clinical context, prior to implementation into clinical practice.

  19. Performance evaluation of laser line scanner for in-process inspection of 3D geometries

    Zhou, Sen; Xu, Jian; Tao, Lei; Yan, Yu

    2016-09-01

    Non-contact measurement techniques using laser scanning have the power to deliver tremendous benefits to most notably manufacturing, and have the advantage of high speed and high detail output. However, a major obstacle to their widespread adoption in more complex on-line producing environments is their geometric constraints and low accuracy compared to the contact-based counterparts. The work presented in this paper introduces a performance evaluation test of laser line scanning for in-process inspection of 3D geometries. Some straightforward test methods that use a designed artifact are proposed. First, one work aims to experimentally investigate the location accuracy of knee point or corner point of edge features using a commercial laser stripe scanner, which is common in mechanical parts. Another work experimentally investigates the formation of outliers that may be usually promoted by reflective surfaces around surrounding area of corner point, and these outliers are characterized with large measurement errors, which significantly deteriorate the quality of the scanned point cloud data. Scanning path planning and outlier filter design are respectively discussed.

  20. Evaluating Dense 3d Reconstruction Software Packages for Oblique Monitoring of Crop Canopy Surface

    Brocks, S.; Bareth, G.

    2016-06-01

    Crop Surface Models (CSMs) are 2.5D raster surfaces representing absolute plant canopy height. Using multiple CMSs generated from data acquired at multiple time steps, a crop surface monitoring is enabled. This makes it possible to monitor crop growth over time and can be used for monitoring in-field crop growth variability which is useful in the context of high-throughput phenotyping. This study aims to evaluate several software packages for dense 3D reconstruction from multiple overlapping RGB images on field and plot-scale. A summer barley field experiment located at the Campus Klein-Altendorf of University of Bonn was observed by acquiring stereo images from an oblique angle using consumer-grade smart cameras. Two such cameras were mounted at an elevation of 10 m and acquired images for a period of two months during the growing period of 2014. The field experiment consisted of nine barley cultivars that were cultivated in multiple repetitions and nitrogen treatments. Manual plant height measurements were carried out at four dates during the observation period. The software packages Agisoft PhotoScan, VisualSfM with CMVS/PMVS2 and SURE are investigated. The point clouds are georeferenced through a set of ground control points. Where adequate results are reached, a statistical analysis is performed.

  1. A global 3-D CTM evaluation of black carbon in the Tibetan Plateau

    C. He

    2014-03-01

    Full Text Available We evaluate the black carbon (BC simulations for 2006 over the Tibetan Plateau by a global 3-D chemical transport model using surface observations of BC in surface air and in snow and BC absorption aerosol optical depth (AAOD. Using updated Asian anthropogenic BC emissions (Lu et al., 2011; Zhang et al., 2009 and global biomass burning emissions (Randerson et al., 2012; van der Werf et al., 2010, model results of both surface BC and BC in snow are statistically in good agreement with observations (biases < 15%. Model results capture the seasonal variation of surface BC concentration, but the observed wintertime high values at rural sites in the Indo-Gangetic Plain are absent in the model. Model results are in general agreement with observations (within a factor of two at remote sites. Model simulated BC concentrations in snow are spatiotemporally consistent with observations at most sites. We find that modeled BC AAOD are significantly lower than observations to the northwest of the Plateau and along the southern slopes of the Himalayas during winter and spring, reflecting model deficiencies in emissions, topography and BC mixing state. We find that anthropogenic emissions strongly affect surface BC concentration and AAOD, while the BC aging mainly affects BC in snow over the Plateau.

  2. Preparation and Evaluation of Gelatin-Chitosan-Nanobioglass 3D Porous Scaffold for Bone Tissue Engineering

    Kanchan Maji

    2016-01-01

    Full Text Available The aim of the present study was to prepare and characterize bioglass-natural biopolymer based composite scaffold and evaluate its bone regeneration ability. Bioactive glass nanoparticles (58S in the size range of 20–30 nm were synthesized using sol-gel method. Porous scaffolds with varying bioglass composition from 10 to 30 wt% in chitosan, gelatin matrix were fabricated using the method of freeze drying of its slurry at 40 wt% solids loading. Samples were cross-linked with glutaraldehyde to obtain interconnected porous 3D microstructure with improved mechanical strength. The prepared scaffolds exhibited >80% porosity with a mean pore size range between 100 and 300 microns. Scaffold containing 30 wt% bioglass (GCB 30 showed a maximum compressive strength of 2.2±0.1 MPa. Swelling and degradation studies showed that the scaffold had excellent properties of hydrophilicity and biodegradability. GCB 30 scaffold was shown to be noncytotoxic and supported mesenchymal stem cell attachment, proliferation, and differentiation as indicated by MTT assay and RUNX-2 expression. Higher cellular activity was observed in GCB 30 scaffold as compared to GCB 0 scaffold suggesting the fact that 58S bioglass nanoparticles addition into the scaffold promoted better cell adhesion, proliferation, and differentiation. Thus, the study showed that the developed composite scaffolds are potential candidates for regenerating damaged bone tissue.

  3. Occupant thermal comfort evaluation

    Ghiardi, Gena L.

    1999-03-01

    Throughout the automotive industry there has been an increasing concern and focus on the thermal comfort of occupants. Manufacturers are continuously striving to improve heating and air conditioning performance to comply with expanding customer needs. To optimize these systems, the technology to acquire data must also be enhanced. In this evaluation, the standard use of isolated thermocouple location technology is compared to utilizing infrared thermal vision in an air conditioning performance assessment. Infrared data on an actual occupant is correlated to breath and air conditioning output temperatures measured by positioned thermocouples. The use of infrared thermal vision highlights various areas of comfort and discomfort experienced by the occupant. The evaluation involves utilizing an infrared thermal vision camera to film an occupant in the vehicle as the following test procedure is run. The vehicle is soaked in full sun load until the interior temperature reaches a minimum of 150 degrees F (65.6 degrees Celsius). The occupant enters the vehicle and takes an initial temperature reading. The air conditioning is turned on to full cold, full fan speed, and recirculation mode. While being filmed, the driver drives for sixty minutes at 30 miles per hour (48.3 kph). The thermocouples acquire data in one minute intervals while the infrared camera films the cooling process of the occupant.

  4. Study of the initiation and the propagation of cracks under 3D thermal cyclic loading; Etude de l'amorcage et de la propagation des fissures sous chargement thermique cyclique 3D

    Ancelet, O

    2005-07-01

    The incident which has occurred on the Civaux power plant has shown the noxiousness of thermal loading and the difficulty to take it into account at design level. The objective of this report is to study the initiation and the propagation of crack under thermal loading. In this aim the CEA has developed a new experiment named FAT3D. The various experiments carried out showed the harmfulness of a thermal loading, which makes it possible to rapidly initiate a network of cracks and to propagate one (or some) cracks through the totally thickness of the component under certain conditions. These experimental results associated with a mechanical analysis put at fault the usual criteria of damage based on the variations of the equivalent strain. In addition, the study of the propagation stage shows the importance of the plasticity which, in the case of a thermal loading, slows down the propagation of the crack. (author)

  5. Evaluation of CANDU6 PCR (power coefficient of reactivity) with a 3-D whole-core Monte Carlo Analysis

    Motalab, Mohammad Abdul; Kim, Woosong; Kim, Yonghee, E-mail: yongheekim@kaist.ac.kr

    2015-12-15

    Highlights: • The PCR of the CANDU6 reactor is slightly negative at low power, e.g. <80% P. • Doppler broadening of scattering resonances improves noticeably the FTC and make the PCR more negative or less positive in CANDU6. • The elevated inlet coolant condition can worsen significantly the PCR of CANDU6. • Improved design tools are needed for the safety evaluation of CANDU6 reactor. - Abstract: The power coefficient of reactivity (PCR) is a very important parameter for inherent safety and stability of nuclear reactors. The combined effect of a relatively less negative fuel temperature coefficient and a positive coolant temperature coefficient make the CANDU6 (CANada Deuterium Uranium) PCR very close to zero. In the original CANDU6 design, the PCR was calculated to be clearly negative. However, the latest physics design tools predict that the PCR is slightly positive for a wide operational range of reactor power. It is upon this contradictory observation that the CANDU6 PCR is re-evaluated in this work. In our previous study, the CANDU6 PCR was evaluated through a standard lattice analysis at mid-burnup and was found to be negative at low power. In this paper, the study was extended to a detailed 3-D CANDU6 whole-core model using the Monte Carlo code Serpent2. The Doppler broadening rejection correction (DBRC) method was implemented in the Serpent2 code in order to take into account thermal motion of the heavy uranium nucleus in the neutron-U scattering reactions. Time-average equilibrium core was considered for the evaluation of the representative PCR of CANDU6. Two thermal hydraulic models were considered in this work: one at design condition and the other at operating condition. Bundle-wise distributions of the coolant properties are modeled and the bundle-wise fuel temperature is also considered in this study. The evaluated nuclear data library ENDF/B-VII.0 was used throughout this Serpent2 evaluation. In these Monte Carlo calculations, a large number

  6. Towards Reliable Stereoscopic 3D Quality Evaluation: Subjective Assessment and Objective Metrics

    Xing, Liyuan

    2013-01-01

    Stereoscopic three-dimensional (3D) services have become more popular recently amid promise of providing immersive quality of experience (QoE) to the end-users with the help of binocular depth. However, various arisen artifacts in the stereoscopic 3D processing chain might cause discomfort and severely degrade the QoE. Unfortunately, although the causes and nature of artifacts have already been clearly understood, it is impossible to eliminate them under the limitation of current stereoscopic...

  7. Design and Evaluation of 3D Positioning Techniques for Multi-touch Displays

    Martinet, Anthony; Casiez, Gery; Grisoni, Laurent

    2009-01-01

    Multi-touch displays represent a promising technology for the display and manipulation of 3D data. To fully exploit their capabilities, appropriate interaction techniques must be designed. In this paper, we explore the design of free 3D positioning techniques for multi-touch displays to exploit the additional degrees of freedom provided by this technology. We present a first interaction technique to extend the standard four viewports technique found in commercial CAD applications and a second...

  8. 3-D evaluation of tropospheric ozone simulations by an ensemble of regional Chemistry Transport Model

    D. Zyryanov

    2011-10-01

    Full Text Available A detailed 3-D evaluation of an ensemble of five regional CTM's and one global CTM with focus on free tropospheric ozone over Europe is presented. It is performed over a summer period (June to August 2008 in the context of the GEMS-RAQ project. A data set of about 400 vertical ozone profiles from balloon soundings and commercial aircraft at 11 different locations is used for model evaluation, in addition to satellite measurements with the infrared nadir IASI sounder showing largest sensitivity to free tropospheric ozone. In the free troposphere, models using the same top and boundary conditions from MOZART-IFS exhibit a systematic negative bias with respect to observed profiles of about −20%. RMSE values are constantly growing with altitude, from 22% to 32% to 53%, respectively for 0–2 km, 2–8 km and 8–10 km height ranges. Lowest correlation is found in the free troposphere, with minimum coefficients (R between 0.2 to 0.45 near 8 km, as compared to 0.7 near the surface and similar values around 10 km. Use of hourly instead of monthly chemical boundary conditions generally improves the model skill. Lower tropospheric 0–6 km partial ozone columns derived from IASI show a clear North-South gradient over Europe, which is qualitatively reproduced by the models. Also the temporal variability showing decreasing ozone concentrations in the lower troposphere (0–6 km columns during summer is well catched by models even if systematic bias remains (the value of the bias being also controlled by the type of BC used. A multi-day case study of a through with low tropopause was conducted and showed that both IASI and models were able to resolve strong horizontal gradients of middle and upper tropospheric ozone occurring in the vicinity of an upper tropospheric frontal zone.

  9. Evaluation of the 3d Urban Modelling Capabilities in Geographical Information Systems

    Dogru, A. O.; Seker, D. Z.

    2010-12-01

    Geographical Information System (GIS) Technology, which provides successful solutions to basic spatial problems, is currently widely used in 3 dimensional (3D) modeling of physical reality with its developing visualization tools. The modeling of large and complicated phenomenon is a challenging problem in terms of computer graphics currently in use. However, it is possible to visualize that phenomenon in 3D by using computer systems. 3D models are used in developing computer games, military training, urban planning, tourism and etc. The use of 3D models for planning and management of urban areas is very popular issue of city administrations. In this context, 3D City models are produced and used for various purposes. However the requirements of the models vary depending on the type and scope of the application. While a high level visualization, where photorealistic visualization techniques are widely used, is required for touristy and recreational purposes, an abstract visualization of the physical reality is generally sufficient for the communication of the thematic information. The visual variables, which are the principle components of cartographic visualization, such as: color, shape, pattern, orientation, size, position, and saturation are used for communicating the thematic information. These kinds of 3D city models are called as abstract models. Standardization of technologies used for 3D modeling is now available by the use of CityGML. CityGML implements several novel concepts to support interoperability, consistency and functionality. For example it supports different Levels-of-Detail (LoD), which may arise from independent data collection processes and are used for efficient visualization and efficient data analysis. In one CityGML data set, the same object may be represented in different LoD simultaneously, enabling the analysis and visualization of the same object with regard to different degrees of resolution. Furthermore, two CityGML data sets

  10. A hybrid radial basis function-pseudospectral method for thermal convection in a 3-D spherical shell

    Wright, G. B.

    2010-07-01

    A novel hybrid spectral method that combines radial basis function (RBF) and Chebyshev pseudospectral methods in a "2 + 1" approach is presented for numerically simulating thermal convection in a 3-D spherical shell. This is the first study to apply RBFs to a full 3-D physical model in spherical geometry. In addition to being spectrally accurate, RBFs are not defined in terms of any surface-based coordinate system such as spherical coordinates. As a result, when used in the lateral directions, as in this study, they completely circumvent the pole issue with the further advantage that nodes can be "scattered" over the surface of a sphere. In the radial direction, Chebyshev polynomials are used, which are also spectrally accurate and provide the necessary clustering near the boundaries to resolve boundary layers. Applications of this new hybrid methodology are given to the problem of convection in the Earth\\'s mantle, which is modeled by a Boussinesq fluid at infinite Prandtl number. To see whether this numerical technique warrants further investigation, the study limits itself to an isoviscous mantle. Benchmark comparisons are presented with other currently used mantle convection codes for Rayleigh number (Ra) 7 × 103 and 105. Results from a Ra = 106 simulation are also given. The algorithmic simplicity of the code (mostly due to RBFs) allows it to be written in less than 400 lines of MATLAB and run on a single workstation. We find that our method is very competitive with those currently used in the literature. Copyright 2010 by the American Geophysical Union.

  11. The lithosphere-asthenosphere system beneath Ireland from integrated geophysical-petrological modeling II: 3D thermal and compositional structure

    Fullea, J.; Muller, M. R.; Jones, A. G.; Afonso, J. C.

    2014-02-01

    The lithosphere-asthenosphere boundary (LAB) depth represents a fundamental parameter in any quantitative lithospheric model, controlling to a large extent the temperature distribution within the crust and the uppermost mantle. The tectonic history of Ireland includes early Paleozoic closure of the Iapetus Ocean across the Iapetus Suture Zone (ISZ), and in northeastern Ireland late Paleozoic to early Mesozoic crustal extension, during which thick Permo-Triassic sedimentary successions were deposited, followed by early Cenozoic extrusion of large scale flood basalts. Although the crustal structure in Ireland and neighboring offshore areas is fairly well constrained, with the notable exception of the crust beneath Northern Ireland, the Irish uppermost mantle remains to date relatively unknown. In particular, the nature and extent of a hypothetical interaction between a putative proto Icelandic mantle plume and the Irish and Scottish lithosphere during the Tertiary opening of the North Atlantic has long been discussed in the literature with diverging conclusions. In this work, the present-day thermal and compositional structure of the lithosphere in Ireland is modeled based on a geophysical-petrological approach (LitMod3D) that combines comprehensively a large variety of data (namely elevation, surface heat flow, potential fields, xenoliths and seismic tomography models), reducing the inherent uncertainties and trade-offs associated with classical modeling of those individual data sets. The preferred 3D lithospheric models show moderate lateral density variations in Ireland characterized by a slightly thickened lithosphere along the SW-NE trending ISZ, and a progressive lithospheric thinning from southern Ireland towards the north. The mantle composition in the southern half of Ireland (East Avalonia) is relatively and uniformly fertile (i.e., typical Phanerozoic mantle), whereas the lithospheric composition in the northern half of Ireland (Laurentia) seems to vary

  12. Use and Evaluation of 3D GeoWall Visualizations in Undergraduate Space Science Classes

    Turner, N. E.; Hamed, K. M.; Lopez, R. E.; Mitchell, E. J.; Gray, C. L.; Corralez, D. S.; Robinson, C. A.; Soderlund, K. M.

    2005-12-01

    One persistent difficulty many astronomy students face is the lack of 3- dimensional mental model of the systems being studied, in particular the Sun-Earth-Moon system. Students without such a mental model can have a very hard time conceptualizing the geometric relationships that cause, for example, the cycle of lunar phases or the pattern of seasons. The GeoWall is a recently developed and affordable projection mechanism for three-dimensional stereo visualization which is becoming a popular tool in classrooms and research labs for use in geology classes, but as yet very little work has been done involving the GeoWall for astronomy classes. We present results from a large study involving over 1000 students of varied backgrounds: some students were tested at the University of Texas at El Paso, a large public university on the US-Mexico border and other students were from the Florida Institute of Technology, a small, private, technical school in Melbourne Florida. We wrote a lecture tutorial-style lab to go along with a GeoWall 3D visual of the Earth-Moon system and tested the students before and after with several diagnostics. Students were given pre and post tests using the Lunar Phase Concept Inventory (LPCI) as well as a separate evaluation written specifically for this project. We found the lab useful for both populations of students, but not equally effective for all. We discuss reactions from the students and their improvement, as well as whether the students are able to correctly assess the usefullness of the project for their own learning.

  13. 3D FIESTA联合3D TOF MRA对三叉神经血管压迫的诊断价值%Diagnostic value of MRI 3D FIESTA combined with 3D TOF MRA sequence in evaluation of the trigeminal neurovas-cular compression

    朱敏; 周小飞; 李平

    2015-01-01

    目的:探讨MRI 3D循环相位稳态采集快速成像(FIESTA)序列联合3D TOF MRA序列对三叉神经血管压迫的诊断价值。方法:选取以原发性三叉神经痛就诊的患者25例,均行3D FIESTA和3D TOF MRA。由2名有经验的影像诊断医师在不知道临床症状的情况下对图像进行观察,分析2种序列中三叉神经和邻近血管的走行关系,以评价2种序列联合显示神经血管压迫与临床症状的相关性。结果:20例行手术治疗,与手术结果对照,MRI对血管压迫诊断的阳性符合率为78.9%(15/19),另4例为假阳性(21.1%,4/19);1例术前MRI诊断未见明确神经血管压迫者术中得到证实。5例术前MRI诊断无神经血管压迫的患者未行手术治疗。结论:MRI 3D FIESTA联合3D TOF MRA可清晰显示三叉神经的血管压迫情况,且与临床症状具较好相关性,可帮助临床医师进行术前评估。%Objective:To investigate the value of MRI 3D fast imaging employing steady-state (3D FIESTA) sequence combined with 3D time of flight magnetic resonance angiography (3D TOF MRA) in diagnosis of trigeminal neurovascular compression. Methods:25 cases of primary trigeminal neuralgia patients were examined by MRI (including 3D FIESTA and 3D TOF MRA). The images were reviewed by two experienced radiologists. The spatial relationships between the trigeminal nerve and adjacent vessels were overviewed,in order to evaluate the relevance between neurovascular compression and clinical symptoms. Results:20 cases were received microvacular decompression surgery. The presence of vascular compression were confirmed in 15 cases , with the positive coincidence rate of 78.9% (15/19),another 4 cases of false positive (21.1%,4/19). While the remain 1 case with diagnosis of no neurovascular compression was proved by surgery. 5 cases with preoperative MRI diagnosis of no neu-rovascular compression did not receive operation treatment. Conclusions

  14. Evaluation of Jumping and Creeping Regularization Approaches Applied to 3D Seismic Tomography

    Liu, M.; Ramachandran, K.

    2011-12-01

    are evaluated on a synthetic 3-D true model obtained from a large scale experiment. The evaluation is performed for jumping and creeping approaches for various levels of smoothing constraints, and initial models. The final models are compared against the true models to compute residual distance between the models. Horizontal and vertical roughness in the final models are computed and compared with the true model roughness. Correlation between the true and final models is computed to evaluate the similarities of spatial patterns in the models. The study is also used to show that average 1-D models derived from the final models are very close, indicating that this will be an optimal approach to construct 1-D starting models.

  15. Evaluation by quantitative image analysis of anticancer drug activity on multicellular spheroids grown in 3D matrices

    Gomes, Aurélie; Russo, Adrien; Vidal, Guillaume; Demange, Elise; Pannetier, Pauline; Souguir, Zied; Lagarde, Jean-Michel; Ducommun, Bernard; Lobjois, Valérie

    2016-01-01

    Pharmacological evaluation of anticancer drugs using 3D in vitro models provides invaluable information for predicting in vivo activity. Artificial matrices are currently available that scale up and increase the power of such 3D models. The aim of the present study was to propose an efficient and robust imaging and analysis pipeline to assess with quantitative parameters the efficacy of a particular cytotoxic drug. HCT116 colorectal adenocarcinoma tumor cell multispheres were grown in a 3D physiological hyaluronic acid matrix. 3D microscopy was performed with structured illumination, whereas image processing and feature extraction were performed with custom analysis tools. This procedure makes it possible to automatically detect spheres in a large volume of matrix in 96-well plates. It was used to evaluate drug efficacy in HCT116 spheres treated with different concentrations of topotecan, a DNA topoisomerase inhibitor. Following automatic detection and quantification, changes in cluster size distribution with a topotecan concentration-dependent increase of small clusters according to drug cytotoxicity were observed. Quantitative image analysis is thus an effective means to evaluate and quantify the cytotoxic and cytostatic activities of anticancer drugs on 3D multicellular models grown in a physiological matrix. PMID:28105152

  16. SYDESCO: a laser-video scanner for 3D scoliosis evaluations.

    Treuillet, S; Lucas, Y; Crepin, G; Peuchot, B; Pichaud, J C

    2002-01-01

    SYDESCO is a new 3D vision system developed for trunk surface topography. This structured light surface scanner uses the principle of triangulation-based range sensing to infer 3D shape. The complete trunk acquisition is fast (2 seconds). The accuracy of the metric data is ensured by a subpixel image detection and a calibration process, which rectifies image deformations. A preliminary study presents results on 50 children in a gymnastics school. These children, aged between eight to sixteen years, are particularly exposed to spinal deformities. An asymmetry index is calculated from the 3D data to detect the pathologic cases. These results have been compared to an independent medical diagnosis. The system results have been confirmed for 72,1% of the patients.

  17. Evaluation of the durability of 3D printed keys produced by computational processing of image data

    Straub, Jeremy; Kerlin, Scott

    2016-05-01

    Possession of a working 3D printed key can, for most practical purposes, convince observers that an illicit attempt to gain premises access is authorized. This paper seeks to assess three things. First, work has been performed to determine how easily the data for making models of keys can be obtained through manual measurement. It then presents work done to create a model of the key and determine how easy key modeling could be (particularly after a first key of a given key `blank' has been made). Finally, it seeks to assess the durability of the keys produced using 3D printing.

  18. 3D-2D registration in mobile radiographs: algorithm development and preliminary clinical evaluation

    Otake, Yoshito; Wang, Adam S.; Uneri, Ali; Kleinszig, Gerhard; Vogt, Sebastian; Aygun, Nafi; Lo, Sheng-fu L.; Wolinsky, Jean-Paul; Gokaslan, Ziya L.; Siewerdsen, Jeffrey H.

    2015-03-01

    An image-based 3D-2D registration method is presented using radiographs acquired in the uncalibrated, unconstrained geometry of mobile radiography. The approach extends a previous method for six degree-of-freedom (DOF) registration in C-arm fluoroscopy (namely ‘LevelCheck’) to solve the 9-DOF estimate of geometry in which the position of the source and detector are unconstrained. The method was implemented using a gradient correlation similarity metric and stochastic derivative-free optimization on a GPU. Development and evaluation were conducted in three steps. First, simulation studies were performed that involved a CT scan of an anthropomorphic body phantom and 1000 randomly generated digitally reconstructed radiographs in posterior-anterior and lateral views. A median projection distance error (PDE) of 0.007 mm was achieved with 9-DOF registration compared to 0.767 mm for 6-DOF. Second, cadaver studies were conducted using mobile radiographs acquired in three anatomical regions (thorax, abdomen and pelvis) and three levels of source-detector distance (~800, ~1000 and ~1200 mm). The 9-DOF method achieved a median PDE of 0.49 mm (compared to 2.53 mm for the 6-DOF method) and demonstrated robustness in the unconstrained imaging geometry. Finally, a retrospective clinical study was conducted with intraoperative radiographs of the spine exhibiting real anatomical deformation and image content mismatch (e.g. interventional devices in the radiograph that were not in the CT), demonstrating a PDE = 1.1 mm for the 9-DOF approach. Average computation time was 48.5 s, involving 687 701 function evaluations on average, compared to 18.2 s for the 6-DOF method. Despite the greater computational load, the 9-DOF method may offer a valuable tool for target localization (e.g. decision support in level counting) as well as safety and quality assurance checks at the conclusion of a procedure (e.g. overlay of planning data on the radiograph for verification of

  19. 3-D evaluation of tropospheric ozone simulations by an ensemble of regional Chemistry Transport Model

    D. Zyryanov

    2012-04-01

    Full Text Available A detailed 3-D evaluation of an ensemble of five regional Chemistry Transport Models (RCTM and one global CTM with focus on free tropospheric ozone over Europe is presented. It is performed over a summer period (June to August 2008 in the context of the GEMS-RAQ project. A data set of about 400 vertical ozone profiles from balloon soundings and commercial aircraft at 11 different locations is used for model evaluation, in addition to satellite measurements with the infrared nadir sounder (IASI showing largest sensitivity to free tropospheric ozone. In the middle troposphere, the four regional models using the same top and boundary conditions from IFS-MOZART exhibit a systematic negative bias with respect to observed profiles of about −20%. Root Mean Square Error (RMSE values are constantly growing with altitude, from 22% to 32% to 53%, respectively for 0–2 km, 2–8 km and 8–10 km height ranges. Lowest correlation is found in the middle troposphere, with minimum coefficients (R between 0.2 to 0.45 near 8 km, as compared to 0.7 near the surface and similar values around 10 km. A sensitivity test made with the CHIMERE mode also shows that using hourly instead of monthly chemical boundary conditions generally improves the model skill (i.e. improve RMSE and correlation. Lower tropospheric 0–6 km partial ozone columns derived from IASI show a clear North-South gradient over Europe, which is qualitatively reproduced by the models. Also the temporal variability showing decreasing ozone concentrations in the lower troposphere (0–6 km columns during summer is well reproduced by models even if systematic bias remains (the value of the bias being also controlled by the type of used boundary conditions. A multi-day case study of a trough with low tropopause was conducted and showed that both IASI and models were able to resolve strong horizontal gradients of middle and upper tropospheric ozone occurring in the vicinity of an upper

  20. Clinical evaluation of 3D/3D MRI-CBCT automatching on brain tumors for online patient setup verification - A step towards MRI-based treatment planning

    Buhl, Sune K.; Duun-Christensen, Anne Katrine; Kristensen, Brian H.

    2010-01-01

    Background. Magnetic Resonance Imaging (MRI) is often used in modern day radiotherapy (RT) due to superior soft tissue contrast. However, treatment planning based solely on MRI is restricted due to e. g. the limitations of conducting online patient setup verification using MRI as reference....... In this study 3D/3D MRI-Cone Beam CT (CBCT) automatching for online patient setup verification was investigated. Material and methods. Initially, a multi-modality phantom was constructed and used for a quantitative comparison of CT-CBCT and MRI-CBCT automatching. Following the phantom experiment three patients...

  1. Evaluation of the systematic error in using 3D dose calculation in scanning beam proton therapy for lung cancer.

    Li, Heng; Liu, Wei; Park, Peter; Matney, Jason; Liao, Zhongxing; Chang, Joe; Zhang, Xiaodong; Li, Yupeng; Zhu, Ronald X

    2014-09-08

    The objective of this study was to evaluate and understand the systematic error between the planned three-dimensional (3D) dose and the delivered dose to patient in scanning beam proton therapy for lung tumors. Single-field and multifield optimized scanning beam proton therapy plans were generated for ten patients with stage II-III lung cancer with a mix of tumor motion and size. 3D doses in CT datasets for different respiratory phases and the time-weighted average CT, as well as the four-dimensional (4D) doses were computed for both plans. The 3D and 4D dose differences for the targets and different organs at risk were compared using dose-volume histogram (DVH) and voxel-based techniques, and correlated with the extent of tumor motion. The gross tumor volume (GTV) dose was maintained in all 3D and 4D doses, using the internal GTV override technique. The DVH and voxel-based techniques are highly correlated. The mean dose error and the standard deviation of dose error for all target volumes were both less than 1.5% for all but one patient. However, the point dose difference between the 3D and 4D doses was up to 6% for the GTV and greater than 10% for the clinical and planning target volumes. Changes in the 4D and 3D doses were not correlated with tumor motion. The planning technique (single-field or multifield optimized) did not affect the observed systematic error. In conclusion, the dose error in 3D dose calculation varies from patient to patient and does not correlate with lung tumor motion. Therefore, patient-specific evaluation of the 4D dose is important for scanning beam proton therapy for lung tumors.

  2. Atmospheric correction of thermal-infrared imagery of the 3-D urban environment acquired in oblique viewing geometry

    F. Meier

    2010-12-01

    Full Text Available This research quantifies and discusses atmospheric effects that alter the radiance observed by a ground-based thermal-infrared (TIR camera mounted on top of a high-rise building in the city of Berlin, Germany. The study shows that atmospheric correction of ground-based TIR imagery of the three-dimensional (3-D urban environment acquired in oblique viewing geometry has to account for spatial variability of line-of-sight (LOS geometry. We present an atmospheric correction procedure that uses these spatially distributed LOS geometry parameters, the radiative transfer model MODTRAN 5.2 and atmospheric profile data derived from meteorological measurements in the field of view (FOV of the TIR camera. The magnitude of atmospheric effects varies during the analysed 24-hourly period (8 August 2009 and is particularly notable for surfaces showing a strong surface-to-air temperature difference. The differences between uncorrected and corrected TIR imagery reach up to 7.7 K at 12:00. Atmospheric effects are biased up to 4.3 K at 12:00 and up to 0.6 K at 24:00, if non-spatially distributed LOS parameters are used.

  3. Cranial Base Superimposition for 3D Evaluation of Soft Tissue Changes

    Cevidanes, Lucia H.C.; Motta, Alexandre; Proffit, William R.; Ackerman, James L.; Styner, Martin

    2009-01-01

    The recent emphasis on soft tissues as the limiting factor in treatment and on soft tissue relationships in establishing the goals of treatment has made 3D analysis of soft tissues more important in diagnosis and treatment planning. It is equally important to be able to detect changes in the facial soft tissues produced by growth and/or treatment. This requires structures of reference for superimposition, and a way to display the changes with quantitative information. This paper outlines a technique for quantifying facial soft tissue changes as viewed in CBCT data, using fully-automated voxel-wise registration of the cranial base surface. The assessment of change of soft tissues is done via calculation of the Euclidean surface distances between the 3D models. Color maps are used for visual assessment of the location and quantification of changes. This methodology allows a detailed examination of soft tissue changes with growth and/or treatment. Because of the lack of stable references with 3D photogrammetry, 3D photography and laser scanning, soft tissue changes cannot be accurately quantified by these methods. PMID:20381752

  4. Plaque characterization in ex vivo MRI evaluated by dense 3D correspondence with histology

    van Engelen, Arna; de Bruijne, Marleen; Klein, Stefan;

    2011-01-01

    Automatic quantification of carotid artery plaque composition is important in the development of methods that distinguish vulnerable from stable plaques. MRI has shown to be capable of imaging different components noninvasively. We present a new plaque classification method which uses 3D registra...

  5. Evaluation and Performance Analysis of 3D Printing Technique for Ka-Band Antenna Production

    Armendariz, Unai; Rommel, Simon; Rodríguez Páez, Juan Sebastián

    2016-01-01

    This paper presents the design and fabrication of 3D printed WR-28 waveguide horn antennas operating in the Ka-band frequency range between 26.5GHz and 40GHz. Three antennas are fabricated from polylactide acid filaments in conductive and non-conductive variants; the latter is covered...

  6. Experimental evaluation of ultrasound-guided 3D needle steering in biological tissue

    Abayazid, M.; Vrooijink, G.J.; Patil, Sachin; Alterovitz, Ron; Misra, S.

    2014-01-01

    Purpose In this paper, we present a system capable of automatically steering bevel tip flexible needles under ultrasound guidance toward stationary and moving targets in gelatin phantoms and biological tissue while avoiding stationary and moving obstacles. We use three-dimensional (3D) ultrasound to

  7. Asymmetrically Compressed Stereoscopic 3D Videos: Quality Assessment and Rate-Distortion Performance Evaluation.

    Wang, Jiheng; Wang, Shiqi; Wang, Zhou

    2017-03-01

    Objective quality assessment of stereoscopic 3D video is challenging but highly desirable, especially in the application of stereoscopic video compression and transmission, where useful quality models are missing, that can guide the critical decision making steps in the selection of mixed-resolution coding, asymmetric quantization, and pre- and post-processing schemes. Here we first carry out subjective quality assessment experiments on two databases that contain various asymmetrically compressed stereoscopic 3D videos obtained from mixed-resolution coding, asymmetric transform-domain quantization coding, their combinations, and the multiple choices of postprocessing techniques. We compare these asymmetric stereoscopic video coding schemes with symmetric coding methods and verify their potential coding gains. We observe a strong systematic bias when using direct averaging of 2D video quality of both views to predict 3D video quality. We then apply a binocular rivalry inspired model to account for the prediction bias, leading to a significantly improved full reference quality prediction model of stereoscopic videos. The model allows us to quantitatively predict the coding gain of different variations of asymmetric video compression, and provides new insight on the development of high efficiency 3D video coding schemes.

  8. Using Geometry-Based Metrics as Part of Fitness-for-Purpose Evaluations of 3D City Models

    Wong, K.; Ellul, C.

    2016-10-01

    Three-dimensional geospatial information is being increasingly used in a range of tasks beyond visualisation. 3D datasets, however, are often being produced without exact specifications and at mixed levels of geometric complexity. This leads to variations within the models' geometric and semantic complexity as well as the degree of deviation from the corresponding real world objects. Existing descriptors and measures of 3D data such as CityGML's level of detail are perhaps only partially sufficient in communicating data quality and fitness-for-purpose. This study investigates whether alternative, automated, geometry-based metrics describing the variation of complexity within 3D datasets could provide additional relevant information as part of a process of fitness-for-purpose evaluation. The metrics include: mean vertex/edge/face counts per building; vertex/face ratio; minimum 2D footprint area and; minimum feature length. Each metric was tested on six 3D city models from international locations. The results show that geometry-based metrics can provide additional information on 3D city models as part of fitness-for-purpose evaluations. The metrics, while they cannot be used in isolation, may provide a complement to enhance existing data descriptors if backed up with local knowledge, where possible.

  9. Electrical impedance tomography in 3D using two electrode planes: characterization and evaluation.

    Wagenaar, Justin; Adler, Andy

    2016-06-01

    Electrical impedance tomography (EIT) uses body surface electrical stimulation and measurements to create conductivity images; it shows promise as a non-invasive technology to monitor the distribution of lung ventilation. Most applications of EIT have placed electrodes in a 2D ring around the thorax, and thus produced 2D cross-sectional images. These images are unable to distinguish out-of-plane contributions, or to image volumetric effects. Volumetric EIT can be calculated using multiple electrode planes and a 3D reconstruction algorithm. However, while 3D reconstruction algorithms are available, little has been done to understand the performance of 3D EIT in terms of the measurement configurations available. The goal of this paper is to characterize the phantom and in vivo performance of 3D EIT with two electrode planes. First, phantom measurements are used to measure the reconstruction characteristics of seven stimulation and measurement configurations. Measurements were then performed on eight healthy volunteers as a function of body posture, postures, and with various electrode configurations. Phantom results indicate that 3D EIT using two rings of electrodes provides reasonable resolution in the electrode plane but low vertical resolution. For volunteers, functional EIT images are created from inhalation curve features to analyze the effect of posture (standing, sitting, supine and decline) on regional lung behaviour. An ability to detect vertical changes in lung volume distribution was shown for two electrode configurations. Based on tank and volunteer results, we recommend the use of the 'square' stimulation and measurement pattern for two electrode plane EIT.

  10. Comparison of 2D temperature maps recorded during laser-induced thermal tissue treatment with corresponding temperature distributions calculated from 3D Monte-Carlo simulations

    Busse, Harald; Bublat, Martin; Ratering, Ralf; Rassek, Margarethe; Schwarzmaier, Hans-Joachim; Kahn, Thomas

    2000-05-01

    Minimally invasive techniques often require special biomedical monitoring schemes. In the case of laser coagulation of tumors accurate temperature mapping is desirable for therapy control. While magnetic resonance (MR)-based thermometry can easily yield qualitative results it is still difficult to calibrate this technique with independent temperature probes for the entire 2D field of view. Calculated temperature maps derived from Monte-Carlo simulations (MCS), on the other hand, are suitable for therapy planning and dosimetry but typically can not account for the extract individual tissue parameters and physiological changes upon heating. In this work, online thermometry was combined with MCS techniques to explore the feasibility and potential of such a biomodal approach for surgical assist systems. For the first time, the result of a 3D simulation were evaluated with MR techniques. An MR thermometry system was used to monitor the temperature evolution during laser-induced thermal treatment of bovine liver using a commercially available water-cooled applicator. A systematic comparison between MR-derived 2D temperature maps in different orientations and corresponding snapshots of a 3D MCS of the laser-induced processes is presented. The MCS is capable of resolving the complex temperature patterns observed in the MR-derived images and yields a good agreement with respect to absolute temperatures and damage volume dimensions. The observed quantitative agreement is around 10 degrees C and on the order of 10 percent, respectively. The integrated simulation-and-monitoring approach has the potential to improve surgical assistance during thermal interventions.

  11. Evaluation of dosimetric misrepresentations from 3D conventional planning of liver SBRT using 4D deformable dose integration.

    Yeo, Unjin A; Taylor, Michael L; Supple, Jeremy R; Siva, Shankar; Kron, Tomas; Pham, Daniel; Franich, Rick D

    2014-01-01

    The purpose of this study is to evaluate dosimetric errors in 3D conventional plan- ning of stereotactic body radiotherapy (SBRT) by using a 4D deformable image registration (DIR)-based dose-warping and integration technique. Respiratory- correlated 4D CT image sets with 10 phases were acquired for four consecutive patients with five liver tumors. Average intensity projection (AIP) images were used to generate 3D conventional plans of SBRT. Quasi-4D path-integrated dose accumulation was performed over all 10 phases using dose-warping techniques based on DIR. This result was compared to the conventional plan in order to evalu- ate the appropriateness of 3D (static) dose calculations. In addition, we consider whether organ dose metrics derived from contours defined on the average intensity projection (AIP), or on a reference phase, provide the better approximation of the 4D values. The impact of using fewer (3D planning approach overestimated doses to targets by 1.4% to 8.7% (mean 4.2%) and underestimated dose to normal liver by up to 8% (mean -5.5%; range -2.3% to -8.0%), compared to the 4D methodology. The homogeneity of the dose distribution was overestimated when using conventional 3D calculations by up to 24%. OAR doses estimated by 3D planning were, on average, within 10% of the 4D calculations; however, differences of up to 100% were observed. Four-dimensional dose calculation using 3 phases gave a reasonable approximation of that calculated from the full 10 phases for all patients, which is potentially useful from a workload perspective. 4D evaluation showed that conventional 3D planning on an AIP can significantly overestimate target dose (ITV and GTV+5mm), underestimate normal liver dose, and overestimate dose homogeneity. Implementing nonadaptive quasi- 4D dose calculation can highlight the potential limitation of 3D conventional SBRT planning and the resultant misrepresentations of dose in some regions affected by motion and deformation. Where the 4D

  12. Fourier and granulometry methods on 3D images of soil surfaces for evaluating soil aggregate size distribution

    Jensen, T.; Green, O.; Munkholm, Lars Juhl;

    2016-01-01

    The goal of this research is to present and compare two methods for evaluating soil aggregate size distribution based on high resolution 3D images of the soil surface. The methods for analyzing the images are discrete Fourier transform and granulometry. The results of these methods correlate...... with a measured weight distribution of the soil aggregates. The results have shown that it is possible to distinguish between the cultivated and the uncultivated soil surface. A sensor system suitable for capturing in-situ high resolution 3D images of the soil surface is also described. This sensor system...... is based on a SICK LMS111 laser range scanner....

  13. Hausdorff Distance evaluation of orthodontic accessories' streaking artifacts in 3D model superimposition

    José Rino Neto

    2012-10-01

    Full Text Available The aim of this study was to determine whether image artifacts caused by orthodontic metal accessories interfere with the accuracy of 3D CBCT model superimposition. A human dry skull was subjected three times to a CBCT scan: at first without orthodontic brackets (T1, then with stainless steel brackets bonded without (T2 and with orthodontic arch wires (T3 inserted into the brackets' slots. The registration of image surfaces and the superimposition of 3D models were performed. Within-subject surface distances between T1-T2, T1-T3 and T2-T3 were computed and calculated for comparison among the three data sets. The minimum and maximum Hausdorff Distance units (HDu computed between the corresponding data points of the T1 and T2 CBCT 3D surface images were 0.000000 and 0.049280 HDu, respectively, and the mean distance was 0.002497 HDu. The minimum and maximum Hausdorff Distances between T1 and T3 were 0.000000 and 0.047440 HDu, respectively, with a mean distance of 0.002585 HDu. In the comparison between T2 and T3, the minimum, maximum and mean Hausdorff Distances were 0.000000, 0.025616 and 0.000347 HDu, respectively. In the current study, the image artifacts caused by metal orthodontic accessories did not compromise the accuracy of the 3D model superimposition. Color-coded maps of overlaid structures complemented the computed Hausdorff Distances and demonstrated a precise fusion between the data sets.

  14. Early detection of liver fibrosis in rats using 3-D ultrasound Nakagami imaging: a feasibility evaluation.

    Ho, Ming-Chih; Tsui, Po-Hsiang; Lee, Yu-Hsin; Chen, Yung-Sheng; Chen, Chiung-Nien; Lin, Jen-Jen; Chang, Chien-Cheng

    2014-09-01

    We investigated the feasibility of using 3-D ultrasound Nakagami imaging to detect the early stages of liver fibrosis in rats. Fibrosis was induced in livers of rats (n = 60) by intraperitoneal injection of 0.5% dimethylnitrosamine (DMN). Group 1 was the control group, and rats in groups 2-6 received DMN injections for 1-5 weeks, respectively. Each rat was sacrificed to perform 3-D ultrasound scanning of the liver in vitro using a single-element transducer of 6.5 MHz. The 3-D raw data acquired at a sampling rate of 50 MHz were used to construct 3-D Nakagami images. The liver specimen was further used for histologic analysis with hematoxylin and eosin and Masson staining to score the degree of liver fibrosis. The results indicate that the Metavir scores of the hematoxylin and eosin-stained sections in Groups 1-4 were 0 (defined as early liver fibrosis in this study), and those in groups 5 and 6 ranged from 1 to 2 and 2 to 3, respectively. To quantify the degree of early liver fibrosis, the histologic sections with Masson stain were analyzed to calculate the number of fiber-related blue pixels. The number of blue pixels increased from (2.36 ± 0.79) × 10(4) (group 1) to (7.68 ± 2.62) × 10(4) (group 4) after DMN injections for 3 weeks, indicating that early stages of liver fibrosis were successfully induced in rats. The Nakagami parameter increased from 0.36 ± 0.02 (group 1) to 0.55 ± 0.03 (group 4), with increasing numbers of blue pixels in the Masson-stained sections (p-value Nakagami imaging has potential in the early detection of liver fibrosis in rats and may serve as an image-based pathologic model to visually track fibrosis formation and growth.

  15. A procedure for the evaluation of 2D radiographic texture analysis to assess 3D bone micro-architecture

    Apostol, Lian; Peyrin, Francoise; Yot, Sophie; Basset, Olivier; Odet, Christophe; Tabary, Joachim; Dinten, Jean-Marc; Boller, Elodie; Boudousq, Vincent; Kotzki, Pierre-Olivier

    2004-05-01

    Although the diagnosis of osteoporosis is mainly based on Dual X-ray Absorptiometry, it has been shown that trabecular bone micro-architecture is also an important factor in regards of fracture risk, which can be efficiently assessed in vitro using three-dimensional x-ray microtomography (μCT). In vivo, techniques based on high-resolution s-ray radiography associated to texture analysis have been proposed to investigate bone micro-architecture, but their relevance for giving pertinent 3D information is unclear. The purpose of this work was to develop a method for evaluating the relationships betweeen 3D micro-architecture and 2D texture parameters, and optimizing the conditions for radiographic imaging. Bone sample images taken from cortical to cortical were acquired using 3D-synchrotron x-ray μCT at the ESRF. The 3D digital imagees were further used for two purposes: 1) quantification of three-dimensional bone micro-architecture, 2) simulation of realistic x-ray radiographs under different acquisition conditions. Texture analysis was then applied to these 2D radiographs using a large variety of methods (co-occurence, spectrum, fractal...). First results of the statistical analysis between 2D and 3D parameters allowed identfying the most relevant 2D texture parameters.

  16. Quantitative evaluation of an automatic segmentation method for 3D reconstruction of intervertebral scoliotic disks from MR images

    Claudia Chevrefils

    2012-08-01

    Full Text Available Abstract Background For some scoliotic patients the spinal instrumentation is inevitable. Among these patients, those with stiff curvature will need thoracoscopic disk resection. The removal of the intervertebral disk with only thoracoscopic images is a tedious and challenging task for the surgeon. With computer aided surgery and 3D visualisation of the interverterbral disk during surgery, surgeons will have access to additional information such as the remaining disk tissue or the distance of surgical tools from critical anatomical structures like the aorta or spinal canal. We hypothesized that automatically extracting 3D information of the intervertebral disk from MR images would aid the surgeons to evaluate the remaining disk and would add a security factor to the patient during thoracoscopic disk resection. Methods This paper presents a quantitative evaluation of an automatic segmentation method for 3D reconstruction of intervertebral scoliotic disks from MR images. The automatic segmentation method is based on the watershed technique and morphological operators. The 3D Dice Similarity Coefficient (DSC is the main statistical metric used to validate the automatically detected preoperative disk volumes. The automatic detections of intervertebral disks of real clinical MR images are compared to manual segmentation done by clinicians. Results Results show that depending on the type of MR acquisition sequence, the 3D DSC can be as high as 0.79 (±0.04. These 3D results are also supported by a 2D quantitative evaluation as well as by robustness and variability evaluations. The mean discrepancy (in 2D between the manual and automatic segmentations for regions around the spinal canal is of 1.8 (±0.8 mm. The robustness study shows that among the five factors evaluated, only the type of MRI acquisition sequence can affect the segmentation results. Finally, the variability of the automatic segmentation method is lower than the variability associated

  17. Evaluation of right ventricular volume and function by 2D and 3D echocardiography compared to MRI

    Kjaergaard, Jesper; Petersen, Claus Leth; Kjaer, Andreas;

    2005-01-01

    AIMS: Radionuclide techniques, and recently MRI, have been used for clinical evaluation of right ventricular (RV) volumes function (RVEF) and volumes; but with the introduction of 3D echocardiography, new echocardiographic possibilities for RV evaluation independent of geometrical assumptions have...... emerged. This study compared classic and new echocardiographic and radionuclide estimates, including gated blood pool single-photon emission computed tomography (SPECT) of RV size and function to RV volumes, and ejection fraction (RVEF) measured by magnetic resonance imaging (MRI). METHODS AND RESULTS...

  18. A global 3-D CTM evaluation of black carbon in the Tibetan Plateau

    He, C.; Li, Q. B.; Liou, K. N.; Zhang, J.; Qi, L.; Mao, Y.; Gao, M.; Lu, Z.; Streets, D. G.; Zhang, Q.; Sarin, M. M.; Ram, K.

    2014-07-01

    We systematically evaluate the black carbon (BC) simulations for 2006 over the Tibetan Plateau by a global 3-D chemical transport model (CTM) (GEOS-Chem) driven by GEOS-5 assimilated meteorological fields, using in situ measurements of BC in surface air, BC in snow, and BC absorption aerosol optical depth (AAOD). Using improved anthropogenic BC emission inventories for Asia that account for rapid technology renewal and energy consumption growth (Zhang et al., 2009; Lu et al., 2011) and improved global biomass burning emission inventories that account for small fires (van der Werf et al., 2010; Randerson et al., 2012), we find that model results of both BC in surface air and in snow are statistically in good agreement with observations (biases factor of 2 of the observations at remote sites. Part of the discrepancy is explained by the deficiencies of the meteorological fields over the complex Tibetan terrain. We find that BC concentrations in snow computed from modeled BC deposition and GEOS-5 precipitation are spatiotemporally consistent with observations (r = 0.85). The computed BC concentrations in snow are a factor of 2-4 higher than the observations at several Himalayan sites because of excessive BC deposition. The BC concentrations in snow are biased low by a factor of 2 in the central plateau, which we attribute to the absence of snow aging in the CTM and strong local emissions unaccounted for in the emission inventories. Modeled BC AAOD is more than a factor of 2 lower than observations at most sites, particularly to the northwest of the plateau and along the southern slopes of the Himalayas in winter and spring, which is attributable in large part to underestimated emissions and the assumption of external mixing of BC aerosols in the model. We find that assuming a 50% increase of BC absorption associated with internal mixing reduces the bias in modeled BC AAOD by 57% in the Indo-Gangetic Plain and the northeastern plateau and to the northeast of the plateau

  19. In vivo 3D neuroanatomical evaluation of periprostatic nerve plexus with 3T-MR Diffusion Tensor Imaging

    Panebianco, Valeria, E-mail: valeria.panebianco@gmail.com [Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Viale Regina Elena, 324, 00161 Rome (Italy); Barchetti, Flavio [Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Viale Regina Elena, 324, 00161 Rome (Italy); Sciarra, Alessandro [Department of Urology, Sapienza University of Rome (Italy); Marcantonio, Andrea; Zini, Chiara [Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Viale Regina Elena, 324, 00161 Rome (Italy); Salciccia, Stefano [Department of Urology, Sapienza University of Rome (Italy); Collettini, Federico [Department of Radiology, Charité, Berlin (Germany); Gentile, Vincenzo [Department of Urology, Sapienza University of Rome (Italy); Hamm, Bernard [Department of Radiology, Charité, Berlin (Germany); Catalano, Carlo [Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Viale Regina Elena, 324, 00161 Rome (Italy)

    2013-10-01

    Objectives: To evaluate if Diffusion Tensor Imaging technique (DTI) can improve the visualization of periprostatic nerve fibers describing the location and distribution of entire neurovascular plexus around the prostate in patients who are candidates for prostatectomy. Materials and methods: Magnetic Resonance Imaging (MRI), including a 2D T2-weighted FSE sequence in 3 planes, 3D T2-weighted and DTI using 16 gradient directions and b = 0 and 1000, was performed on 36 patients. Three out of 36 patients were excluded from the analysis due to poor image quality (blurring N = 2, artifact N = 1). The study was approved by local ethics committee and all patients gave an informed consent. Images were evaluated by two radiologists with different experience in MRI. DTI images were analyzed qualitatively using dedicated software. Also 2D and 3D T2 images were independently considered. Results: 3D-DTI allowed description of the entire plexus of the periprostatic nerve fibers in all directions, while 2D and 3D T2 morphological sequences depicted part of the fibers, in a plane by plane analysis of fiber courses. DTI demonstrated in all patients the dispersion of nerve fibers around the prostate on both sides including the significant percentage present in the anterior and anterolateral sectors. Conclusions: DTI offers optimal representation of the widely distributed periprostatic plexus. If validated, it may help guide nerve-sparing radical prostatectomy.

  20. Evaluation of the use of 3D printing and imaging to create working replica keys

    Straub, Jeremy; Kerlin, Scott

    2016-06-01

    This paper considers the efficacy of 3D scanning and printing technologies to produce duplicate keys. Duplication of keys, based on remote-sensed data represents a significant security threat, as it removes pathways to determining who illicitly gained access to a secured premises. Key to understanding the threat posed is the characterization of the easiness of gaining the required data for key production and an understanding of how well keys produced under this method work. The results of an experiment to characterize this are discussed and generalized to different key types. The effect of alternate sources of data on imaging requirements is considered.

  1. Mechanical evaluation of gradient electrospun scaffolds with 3D printed ring reinforcements for tracheal defect repair.

    Ott, Lindsey M; Zabel, Taylor A; Walker, Natalie K; Farris, Ashley L; Chakroff, Jason T; Ohst, Devan G; Johnson, Jed K; Gehrke, Steven H; Weatherly, Robert A; Detamore, Michael S

    2016-04-21

    Tracheal stenosis can become a fatal condition, and current treatments include augmentation of the airway with autologous tissue. A tissue-engineered approach would not require a donor source, while providing an implant that meets both surgeons' and patients' needs. A fibrous, polymeric scaffold organized in gradient bilayers of polycaprolactone (PCL) and poly-lactic-co-glycolic acid (PLGA) with 3D printed structural ring supports, inspired by the native trachea rings, could meet this need. The purpose of the current study was to characterize the tracheal scaffolds with mechanical testing models to determine the design most suitable for maintaining a patent airway. Degradation over 12 weeks revealed that scaffolds with the 3D printed rings had superior properties in tensile and radial compression, with at least a three fold improvement and 8.5-fold improvement, respectively, relative to the other scaffold groups. The ringed scaffolds produced tensile moduli, radial compressive forces, and burst pressures similar to or exceeding physiological forces and native tissue data. Scaffolds with a thicker PCL component had better suture retention and tube flattening recovery properties, with the monolayer of PCL (PCL-only group) exhibiting a 2.3-fold increase in suture retention strength (SRS). Tracheal scaffolds with ring reinforcements have improved mechanical properties, while the fibrous component increased porosity and cell infiltration potential. These scaffolds may be used to treat various trachea defects (patch or circumferential) and have the potential to be employed in other tissue engineering applications.

  2. CT virtual endoscopy and 3D stereoscopic visualisation in the evaluation of coronary stenting.

    Sun, Z; Lawrence-Brown

    2009-10-01

    The aim of this case report is to present the additional value provided by CT virtual endoscopy and 3D stereoscopic visualisation when compared with 2D visualisations in the assessment of coronary stenting. A 64-year old patient was treated with left coronary stenting 8 years ago and recently followed up with multidetector row CT angiography. An in-stent restenosis of the left coronary artery was suspected based on 2D axial and multiplanar reformatted images. 3D virtual endoscopy was generated to demonstrate the smooth intraluminal surface of coronary artery wall, and there was no evidence of restenosis or intraluminal irregularity. Virtual fly-through of the coronary artery was produced to examine the entire length of the coronary artery with the aim of demonstrating the intraluminal changes following placement of the coronary stent. In addition, stereoscopic views were generated to show the relationship between coronary artery branches and the coronary stent. In comparison with traditional 2D visualisations, virtual endoscopy was useful for assessment of the intraluminal appearance of the coronary artery wall following coronary stent implantation, while stereoscopic visualisation improved observers' understanding of the complex cardiac structures. Thus, both methods could be used as a complementary tool in cardiac imaging.

  3. Evaluation of 3D-human skin equivalents for assessment of human dermal absorption of some brominated flame retardants.

    Abdallah, Mohamed Abou-Elwafa; Pawar, Gopal; Harrad, Stuart

    2015-11-01

    Ethical and technical difficulties inherent to studies in human tissues are impeding assessment of the dermal bioavailability of brominated flame retardants (BFRs). This is further complicated by increasing restrictions on the use of animals in toxicity testing, and the uncertainties associated with extrapolating data from animal studies to humans due to inter-species variations. To overcome these difficulties, we evaluate 3D-human skin equivalents (3D-HSE) as a novel in vitro alternative to human and animal testing for assessment of dermal absorption of BFRs. The percutaneous penetration of hexabromocyclododecanes (HBCD) and tetrabromobisphenol-A (TBBP-A) through two commercially available 3D-HSE models was studied and compared to data obtained for human ex vivo skin according to a standard protocol. No statistically significant differences were observed between the results obtained using 3D-HSE and human ex vivo skin at two exposure levels. The absorbed dose was low (less than 7%) and was significantly correlated with log Kow of the tested BFR. Permeability coefficient values showed increasing dermal resistance to the penetration of γ-HBCD>β-HBCD>α-HBCD>TBBPA. The estimated long lag times (>30 min) suggests that frequent hand washing may reduce human exposure to HBCDs and TBBPA via dermal contact.

  4. Oculomotor paralysis: 3D-CISS MR imaging with MPR in the evaluation of neuralgic manifestation and the adjacent structures

    Sun Xiaoli; Liang Changhu [Shandong Medical Imaging Research Institute, Shandong University, Jing-wu Road No. 324, Jinan 250021 (China); Liu Cheng [Shandong Medical Imaging Research Institute, Shandong University, Jing-wu Road No. 324, Jinan 250021 (China)], E-mail: sdsxl2005@126.com; Liu Shuwei; Deng Kai; He Jingzhen [Shandong Medical Imaging Research Institute, Shandong University, Jing-wu Road No. 324, Jinan 250021 (China)

    2010-02-15

    Purpose: To evaluate the value of three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance (MR) imaging with multi-planar reconstruction (MPR) in displaying the relationship between the oculomotor nerve and its adjacent structures for patients with oculomotor paralysis. Materials and methods: 17 consecutive patients with oculomotor paralysis were examined with 3D-CISS and conventional spin-echo (SE) sequences on a 1.5-Tesla MR system. Original transverse and MPR images were used for image interpretation. The features of the oculomotor nerve and its adjacent structures were identified. The diagnosis was surgically confirmed in all patients. Results: Through 3D-CISS with MPR images, obvious relationship of the oculomotor nerve and its adjacent structures was demonstrated on 17 patients. Of those oculomotor nerves, 15 were compressed by the arteries (n = 15), one by the craniopharyngioma (n = 1), and another one by the neurofibroma (n = 1). Conclusion: 3D-CISS MR imaging with MPR provides an excellent way to characterize the relationship between the nerve and its adjacent structures in the cisternal segment of the oculomotor nerve in the patients with oculomotor paralysis. Moreover, this method shows anatomical details for imaging diagnosis and surgical procedure.

  5. Proposal of a taste evaluating method of the sponge cake by using 3D range sensor

    Kato, Kunihito; Yamamoto, Kazuhiko; Ogawa, Noriko

    2002-10-01

    Nowadays, the image processing techniques are while applying to the food industry in many situations. The most of these researches are applications for the quality control in plants, and there are hardly any cases of measuring the 'taste'. We are developing the measuring system of the deliciousness by using the image sensing. In this paper, we propose the estimation method of the deliciousness of a sponge cake. Considering about the deliciousness of the sponge cake, if the size of the bubbles on the surface is small and the number of them is large, then it is defined that the deliciousness of the sponge cake is better in the field of the food science. We proposed a method of detection bubbles in the surface of the sectional sponge cake automatically by using 3-D image processing. By the statistical information of these detected bubbles based on the food science, the deliciousness is estimated.

  6. Development and Evaluation of Roadside/Obstacle Detection Method Using 3D Scanned Data Processing

    Yamamoto, Hiroshi; Ishii, Yoshinori; Yamazaki, Katsuyuki

    In this paper, we have reported the development of a snowblower support system which can safely navigate snowblowers, even during a whiteout, with the combination of a very accurate GPS system, so called RTK-GPS, and a unique and highly accurate map of roadsides and obstacles on roads. Particularly emphasized new techniques in this paper are ways to detect accurate geographical positions of roadsides and obstacles by utilizing and analyzing 3D laser scanned data, whose data has become available in recent days. The experiment has shown that the map created by the methods and RTK-GPS can sufficiently navigate snowblowers, whereby a secure and pleasant social environment can be archived in snow areas of Japan. In addition, proposed methods are expected to be useful for other systems such as a quick development of a highly accurate road map, a safely navigation of a wheeled chair, and so on.

  7. Characterization of the 3D distribution of ozone and coarse aerosols in the Troposphere using IASI thermal infrared satellite observations

    Cuesta, J.; Eremenko, M.; Dufour, G.; Hoepfner, M.; Orphal, J.

    2012-04-01

    Both tropospheric ozone and aerosols significantly affect air quality in megacities during pollution events. Moreover, living conditions may be seriously aggravated when such agglomerations are affected by wildfires (e.g. Russian fires over Moscow in 2010), which produce smoke and pollutant precursors, or even during dense desert dust outbreaks (e.g. recurrently over Beijing or Cairo). Moreover, since aerosols diffuse and absorb solar radiation, they have a direct impact on the photochemical production of tropospheric ozone. These interactions during extreme events of high aerosol loads are nowadays poorly known, even though they may significantly affect the tropospheric photochemical equilibrium. In order to address these issues, we have developed a new retrieval technique to jointly characterize the 3D distribution of both tropospheric ozone and coarse aerosols, using spaceborne observations of the infrared spectrometer IASI onboard MetOp-A satellite. Our methodology is based on the inversion of Earth radiance spectra in the atmospheric window from 8 to 12 μm measured by IASI and a «Tikhonov-Philipps»-type regularisation with constraints varying in altitude (as in [Eremenko et al., 2008, GRL; Dufour et al., 2010 ACP]) to simultaneously retrieve ozone profiles, aerosol optical depths at 10 μm and aerosol layer effective heights. Such joint retrieval prevents biases in the ozone profile retrieval during high aerosol load conditions. Aerosol retrievals using thermal infrared radiances mainly account for desert dust and the coarse fraction of biomass burning aerosols. We use radiances from 15 micro-windows within the 8-12 μm atmospheric window, which were carefully chosen (following [Worden et al., 2006 JGR]) for extracting the maximum information on aerosols and ozone and minimizing contamination by other species. We use the radiative transfer code KOPRA, including line-by-line calculations of gas absorption and single scattering for aerosols [Hoepfner et al

  8. Multimodal, 3D pathology-mimicking bladder phantom for evaluation of cystoscopic technologies (Conference Presentation)

    Smith, Gennifer T.; Lurie, Kristen L.; Zlatev, Dimitar V.; Liao, Joseph C.; Ellerbee, Audrey K.

    2016-02-01

    Optical coherence tomography (OCT) and blue light cystoscopy (BLC) have shown significant potential as complementary technologies to traditional white light cystoscopy (WLC) for early bladder cancer detection. Three-dimensional (3D) organ-mimicking phantoms provide realistic imaging environments for testing new technology designs, the diagnostic potential of systems, and novel image processing algorithms prior to validation in real tissue. Importantly, the phantom should mimic features of healthy and diseased tissue as they appear under WLC, BLC, and OCT, which are sensitive to tissue color and structure, fluorescent contrast, and optical scattering of subsurface layers, respectively. We present a phantom posing the hollow shape of the bladder and fabricated using a combination of 3D-printing and spray-coating with Dragon Skin (DS) (Smooth-On Inc.), a highly elastic polymer to mimic the layered structure of the bladder. Optical scattering of DS was tuned by addition of titanium dioxide, resulting in scattering coefficients sufficient to cover the human bladder range (0.49 to 2.0 mm^-1). Mucosal vasculature and tissue coloration were mimicked with elastic cord and red dye, respectively. Urethral access was provided through a small hole excised from the base of the phantom. Inserted features of bladder pathology included altered tissue color (WLC), fluorescence emission (BLC), and variations in layered structure (OCT). The phantom surface and underlying material were assessed on the basis of elasticity, optical scattering, layer thicknesses, and qualitative image appearance. WLC, BLC, and OCT images of normal and cancerous features in the phantom qualitatively matched corresponding images from human bladders.

  9. Subjective evaluation of two stereoscopic imaging systems exploiting visual attention to improve 3D quality of experience

    Hanhart, Philippe; Ebrahimi, Touradj

    2014-03-01

    Crosstalk and vergence-accommodation rivalry negatively impact the quality of experience (QoE) provided by stereoscopic displays. However, exploiting visual attention and adapting the 3D rendering process on the fly can reduce these drawbacks. In this paper, we propose and evaluate two different approaches that exploit visual attention to improve 3D QoE on stereoscopic displays: an offline system, which uses a saliency map to predict gaze position, and an online system, which uses a remote eye tracking system to measure real time gaze positions. The gaze points were used in conjunction with the disparity map to extract the disparity of the object-of-interest. Horizontal image translation was performed to bring the fixated object on the screen plane. The user preference between standard 3D mode and the two proposed systems was evaluated through a subjective evaluation. Results show that exploiting visual attention significantly improves image quality and visual comfort, with a slight advantage for real time gaze determination. Depth quality is also improved, but the difference is not significant.

  10. Acquired experience on organizing 3D S.UN.COP: international course to support nuclear license by user training in the areas of scaling, uncertainty, and 3D thermal-hydraulics/neutron-kinetics coupled codes

    Petruzzi, Alessandro; D' Auria, Francesco [University of Pisa, San Piero a Grado (Italy). Nuclear Research Group San Piero a Grado (GRNSPG); Galetti, Regina, E-mail: regina@cnen.gov.b [National Commission for Nuclear Energy (CNEN), Rio de Janeiro, RJ (Brazil); Bajs, Tomislav [University of Zagreb (Croatia). Fac. of Electrical Engineering and Computing. Dept. of Power Systems; Reventos, Francesc [Technical University of Catalonia, Barcelona (Spain). Dept. of Physics and Nuclear Engineering

    2011-07-01

    Thermal-hydraulic system computer codes are extensively used worldwide for analysis of nuclear facilities by utilities, regulatory bodies, nuclear power plant designers, vendors, and research organizations. Computer code user represents a source of uncertainty that may significantly affect the results of system code calculations. Code user training and qualification represent an effective means for reducing the variation of results caused by the application of the codes by different users. This paper describes the experience in applying a systematic approach to training code users who, upon completion of the training, should be able to perform calculations making the best possible use of the capabilities of best estimate codes. In addition, this paper presents the organization and the main features of the 3D S.UN.COP (scaling, uncertainty, and 3D coupled code calculations) seminars during which particular emphasis is given to practical applications in connection with the licensing process of best estimate plus uncertainty methodologies, showing the designer, utility and regulatory approaches. (author)

  11. Use of VAP3D software in the construction of pathological anthropomorphic phantoms for dosimetric evaluations; Uso do software VAP3D na construcao de fantomas antropomorficos patologicos para avaliacoes dosimetricas

    Lima, Lindeval Fernandes de [Universidade Federal de Pernambuco (DEM/UFPE), Recife, PE (Brazil). Dept. de Engenharia Mecanica; Vieira, Jose Wilson [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco, Recife, PE (Brazil); Lima, Fernando R.A., E-mail: falima@cnen.gov.b [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2011-10-26

    This paper performs a new type of dosimetric evaluation, where it was used a phantom of pathological voxels (representative phantom of sick person). The software VAP3D (Visualization and Analysis of Phantoms 3D) were used for, from a healthy phantom (phantom representative of healthy person), to introduce three dimensional regions to simulate tumors. It was used the Monte Carlo ESGnrc code to simulate the X ray photon transport, his interaction with matter and evaluation of absorbed dose in organs and tissues from thorax region of the healthy phantom and his pathological version. This is a computer model of typical exposure for programming the treatments in radiodiagnostic

  12. Fabrication of imitative cracks by 3D printing for electromagnetic nondestructive testing and evaluations

    Noritaka Yusa

    2016-05-01

    Full Text Available This study demonstrates that 3D printing technology offers a simple, easy, and cost-effective method to fabricate artificial flaws simulating real cracks from the viewpoint of eddy current testing. The method does not attempt to produce a flaw whose morphology mirrors that of a real crack but instead produces a relatively simple artificial flaw. The parameters of this flaw that have dominant effects on eddy current signals can be quantitatively controlled. Three artificial flaws in type 316L austenitic stainless steel plates were fabricated using a powderbed-based laser metal additive manufacturing machine. The three artificial flaws were designed to have the same length, depth, and opening but different branching and electrical contacts between flaw surfaces. The flaws were measured by eddy current testing using an absolute type pancake probe. The signals due to the three flaws clearly differed from each other although the flaws had the same length and depth. These results were supported by subsequent destructive tests and finite element analyses.

  13. Close-range optical measurement of aircraft's 3D attitude and accuracy evaluation

    Zhe Li; Zhenliang Ding; Feng Yuan

    2008-01-01

    A new screen-spot imaging method based on optical measurement is proposed, which is applicable to the close-range measurement of aircraft's three-dimensional (3D) attitude parameters. Laser tracker is used to finish the global calibrations of the high-speed cameras and the fixed screens on test site, as well as to establish media-coordinate-frames among various coordinate systems. The laser cooperation object mounted on the aircraft surface projects laser beams on the screens and the high-speed cameras syn-chronously record the light-spots' position changing with aircraft attitude. The recorded image sequences are used to compute the aircraft attitude parameters. Based on the matrix analysis, the error sources of the measurement accuracy are analyzed, and the maximum relative error of this mathematical model is estimated. The experimental result shows that this method effectively makes the change of aircraft position distinguishable, and the error of this method is no more than 3' while the rotation angles of three axes are within a certain range.

  14. A 3D quantitative evaluation for assessing the changes of treatment planning system and irradiation techniques in radiotherapy

    Abdulhamid Chaikh

    2014-08-01

    Full Text Available Purpose: This work proposes and compares two 3D global evaluation methods for assessing the alteration of calculated dose distributions when treatment planning system algorithms or irradiation techniques is modified in radiation therapy. Methods: The global analysis is based on gamma index (γ proposed by Low et al.1 and Chi (χ index proposed by Bakai et al.2. The γ and χ values are signed in order to identify the over and under estimating dosage. The 3D maps, the cumulative Gamma Voxels Histograms (GVHs and Chi Voxels Histograms (CVHs were generated using two software. The γ and χ criteria were set to 3 mm for the distance to agreement and 3% for dose. Pearson's Chi-squared test was applied to assess the statistically significance between GVHs and CVHs. We illustrated this method for the change of dose calculation algorithms for lung cancer, and the change of irradiation techniques for breast cancer. For each patient, 2 treatment plans were generated. For the example of change of dose calculation algorithms, a plan 1 was calculated using Pencil Beam Convolution (PBC algorithm and a plan 2 was calculated using Modified Batho method (PBC-MB. For the example of change of irradiation technique, a plan 1 was calculated using Source Skin Distance SSD technique and a plan 2 was calculated using a single isocenter technique. Results: The 3D analysis based on γ and χ indexes showed a significant effect on the dosimetric representation in the lung cancer when we change the PBC algorithm to PBC-MB method. The comparison between the two irradiation techniques showed that the single isocenter technique produces a better dose distribution for the treatment of breast cancer. Pearson's Chi-squared test showed that there was no statistically significance between GVHs and CVHs generated by γ and χ indexes, (p > 0.05. The global analysis using 3D for γ and χ indexes confirmed the results obtained from dosimetric analysis. Conclusion: The methods

  15. Dual-projection 3D-2D registration for surgical guidance: preclinical evaluation of performance and minimum angular separation

    Uneri, A.; Otake, Y.; Wang, A. S.; Kleinszig, G.; Vogt, S.; Gallia, G. L.; Rigamonti, D.; Wolinsky, J.-P.; Gokaslan, Ziya L.; Khanna, A. J.; Siewerdsen, J. H.

    2014-03-01

    An algorithm for 3D-2D registration of CT and x-ray projections has been developed using dual projection views to provide 3D localization with accuracy exceeding that of conventional tracking systems. The registration framework employs a normalized gradient information (NGI) similarity metric and covariance matrix adaptation evolution strategy (CMAES) to solve for the patient pose in 6 degrees of freedom. Registration performance was evaluated in anthropomorphic head and chest phantoms, as well as a human torso cadaver, using C-arm projection views acquired at angular separations (Δ𝜃) ranging 0-178°. Registration accuracy was assessed in terms target registration error (TRE) and compared to that of an electromagnetic tracker. Studies evaluated the influence of C-arm magnification, x-ray dose, and preoperative CT slice thickness on registration accuracy and the minimum angular separation required to achieve TRE ~2 mm. The results indicate that Δ𝜃 as small as 10-20° is adequate to achieve TRE registration of preoperative CT and planning data to intraoperative fluoroscopy, providing 3D localization free from conventional limitations associated with external fiducial markers, stereotactic frames, trackers, and manual registration. The studies support potential application to percutaneous spine procedures and intracranial neurosurgery.

  16. Evaluation of usefulness and availability for orthopedic surgery using clavicle fracture model manufactured by desktop 3D printer

    Oh, Wang Kyun [Dept. of Diagnostic Radiology, Cheongju Medical Center, Cheongju (Korea, Republic of)

    2014-09-15

    Usefulness and clinical availability for surgery efficiency were evaluated by conducting pre-operative planning with a model manufactured by desktop 3D printer by using clavicle CT image. The patient-customized clavicle fracture model was manufactured by desktop 3D printer of FDM wire laminated processing method by converting the CT image into STL file in Open Source DICOM Viewer Osirix. Also, the model of the original shape before damaged was restored and manufactured by Mirror technique based on STL file of not fractured clavicle of the other side by using the symmetry feature of the human body. For the model, the position and size, degree of the fracture was equally printed out. Using the clavicle model directly manufactured with low cost and less time in Department of Radiology is considered to be useful because it can reduce secondary damage during surgery and increase surgery efficiency with Minimal invasive percutaneous plate osteosynthesis(MIPO)

  17. Improved treatments for evaluating horizontal magnetic components through the 3-D FDM in E-polarization induction problems

    陈伯舫

    2002-01-01

    To improve the accuracy of the numerical evaluation through the 3-D finite difference method, the surface boundary conditions are added to modify the old program. The author has tested the new program by making calculations for the model constructed by Wanamaker, et al (1984). The comparison between the numerical results obtained from this paper and those by Wannamaker, et al (1984) indicates that a pronounced improvement is realized in the evaluation of the horizontal magnetic components. Moreover, better calculations for the vertical magnetic components are also obtainable by using the new program.

  18. Evaluation of occlusal rest seats with 3D technology in dental education.

    Sampaio-Fernandes, Manuel António Ferreira; Sampaio-Fernandes, Maria M; Fonseca, Patrícia A; Almeida, Paulo R; Reis-Campos, José C; Figueiral, Maria H

    2015-02-01

    The preparation of rest seats must comply with specific sizes and shapes. Various technological systems such as Kavo PrepAssistant have been used as an auxiliary method to evaluate preclinical preparations more objectively. The aims of this study were to establish an alternative system for evaluating occlusal rest seats and to compare different types of assessment. Seventy-six undergraduate students at Oporto University Faculty of Dental Medicine in Portugal were selected as a convenience sample to prepare two occlusal rest seats in Kavo teeth #45 and #46 (FDI World Dental Federation ISO-3950) and were randomly assigned to two groups. Bearing in mind the ideal characteristics of rest seats, the investigators defined ten assessment parameters, and their evaluation weights were independently estimated by three evaluators. Four of these parameters were measured in Kavo PrepAssistant. The results of the different evaluation methods and evaluators varied considerably. The classical evaluation presented final results worse than those of the evaluations using parameters. In this study, carrying out the assessment with Kavo PrepAssistant helped to achieve a more objective and less evaluator-dependent final evaluation.

  19. Technical Note: Immunohistochemical evaluation of mouse brain irradiation targeting accuracy with 3D-printed immobilization device

    Zarghami, Niloufar, E-mail: nzargham@uwo.ca; Jensen, Michael D. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Talluri, Srikanth; Dick, Frederick A. [Department of Biochemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Foster, Paula J. [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Chambers, Ann F. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Wong, Eugene [Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada)

    2015-11-15

    Purpose: Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy of this device for the purpose of mouse brain irradiation. Methods: A mouse head holder was designed for a microCT couch using CAD software and printed in an acrylic based material. Ten mice received half-brain radiation while positioned in the 3D-printed head holder. Animal placement was achieved using on-board image guidance and computerized asymmetric collimators. To evaluate the precision of beam localization for half-brain irradiation, mice were sacrificed approximately 30 min after treatment and brain sections were stained for γ-H2AX, a marker for DNA breaks. The distance and angle of the γ-H2AX radiation beam border to longitudinal fissure were measured on histological samples. Animals were monitored for any possible trauma from the device. Results: Visualization of the radiation beam on ex vivo brain sections with γ-H2AX immunohistochemical staining showed a sharp radiation field within the tissue. Measurements showed a mean irradiation targeting error of 0.14 ± 0.09 mm (standard deviation). Rotation between the beam axis and mouse head was 1.2° ± 1.0° (standard deviation). The immobilization device was easily adjusted to accommodate different sizes of mice. No signs of trauma to the mice were observed from the use of tooth block and ear bars. Conclusions: The authors designed and built a novel 3D-printed mouse head holder with many desired features for accurate and reproducible radiation targeting. The 3D printing technology was found to be practical and economical for producing a small animal imaging and radiation restraint device and allows for customization for study specific needs.

  20. One-step reconstruction with a 3D-printed, biomechanically evaluated custom implant after complex pelvic tumor resection.

    Wong, K C; Kumta, S M; Geel, N V; Demol, J

    2015-01-01

    Resection of a pelvic tumor is challenging because of its complex three-dimensional (3D) anatomy and deep-seated location with nearby vital structures. The resection is technically demanding if a custom implant is used for reconstruction of the bone defect as the surgeon needs to ensure the resection margin is sufficiently wide and the orientation of intended resection planes must match that of the custom implant. We describe a novel workflow of performing a partial acetabular resection in a patient with pelvic chondrosarcoma and reconstruction with a custom pelvic implant in a one-step operation. A multi-planar bone resection was virtually planned. A computer-aided design implant that both matched the bone defect and biomechanically evaluated was prefabricated with 3D printing technology. The 3D-printed patient-specific instruments (PSIs) were used to reproduce the same planned resection. The histology of the tumor specimen showed a clear resection margin. The errors of the achieved resection and implant position were deviating (1-4 mm) from the planned. The patient could walk unaided with a good hip function. No tumor recurrence and implant loosening were noted at 11 months after surgery. The use of this novel CT-based method for surgical planning, the engineering software for implant design and validation, together with 3D printing technology for implant and PSI fabrication makes it possible to generate a personalized, biomechanically evaluated implant for accurate reconstruction after a pelvic tumor resection in a one-step operation. Further study in a larger population is needed to assess the clinical efficacy of the workflow in complex bone tumor surgery.

  1. 3D thermal hydraulic simulation of the hot channel of a typical material testing reactor under normal operation conditions

    El-Morshedy, Salah El-Din; Salama, Amgad [Atomic Energy Authority, Cairo (Egypt). Reactors Dept.

    2010-09-15

    The hot channel in a typical Material Testing Reactor (MTR) is subjected to 3D simulation. Because of the existence of similarity planes, only a quarter of the hot channel including meat thickness, clad, and coolant channel is considered for CFD analysis using the FLUENT code. For the simulation, steady state normal operation regime at the reactor nominal power is assumed. In order to build confidence in our modeling approach, the results obtained in this work are compared with those obtained from the one-dimensional simulation code, MTRTHA. That is, modified variables were generated in order to match those obtained by MTRTHA and to allow comparisons. Quite good agreement is generally observed, however, the maximum clad surface temperature predicted by the 3D calculations, located at the clad mid-width, is higher than the 1D prediction by about 8 C but still below the onset of subcooled boiling by adequate safety margin. The results show quite interesting 3D patterns in both the flow field and the heat transfer. Temperature profiles, velocity profiles and contours are all presented to highlight the essential 3D features of this system. (orig.)

  2. An evaluation of 3D head pose estimation using the Microsoft Kinect v2.

    Darby, John; Sánchez, María B; Butler, Penelope B; Loram, Ian D

    2016-07-01

    The Kinect v2 sensor supports real-time non-invasive 3D head pose estimation. Because the sensor is small, widely available and relatively cheap it has great potential as a tool for groups interested in measuring head posture. In this paper we compare the Kinect's head pose estimates with a marker-based record of ground truth in order to establish its accuracy. During movement of the head and neck alone (with static torso), we find average errors in absolute yaw, pitch and roll angles of 2.0±1.2°, 7.3±3.2° and 2.6±0.7°, and in rotations relative to the rest pose of 1.4±0.5°, 2.1±0.4° and 2.0±0.8°. Larger head rotations where it becomes difficult to see facial features can cause estimation to fail (10.2±6.1% of all poses in our static torso range of motion tests) but we found no significant changes in performance with the participant standing further away from Kinect - additionally enabling full-body pose estimation - or without performing face shape calibration, something which is not always possible for younger or disabled participants. Where facial features remain visible, the sensor has applications in the non-invasive assessment of postural control, e.g. during a programme of physical therapy. In particular, a multi-Kinect setup covering the full range of head (and body) movement would appear to be a promising way forward.

  3. A 3D Lumped Thermal Network Model for Long-term Load Profiles Analysis in High Power IGBT Modules

    Bahman, Amir Sajjad; Ma, Ke; Ghimire, Pramod;

    2016-01-01

    three-dimensional RC lumped thermal network for the high power IGBT modules. The thermal-coupling effects among the chips and among the critical layers are modelled, and boundary conditions including the cooling conditions are also taken into account. It is concluded that, the proposed thermal model...

  4. A protocol for evaluating the accuracy of 3D body scanners

    Kouchi, M.; Mochimaru, M.; Bradtmiller, B.; Daanen, H.A.M.; Li, P.; Nacher, B.; Nam, Y.

    2012-01-01

    Scan-derived landmarks locations and surface shapes are more and more used, but there is no commonly accepted protocol for evaluating the accuracy of these measurements. Therefore we propose a protocol for evaluating the accuracy of surface shape and the repeatability of scan-derived landmark locati

  5. Perceptual Evaluation of Photo-Realism in Real-Time 3D Augmented Reality

    Borg, Mathias; Paprocki, Martin Marko; Madsen, Claus B.

    2014-01-01

    We present a framework for creating photo-realism of three-dimensional augmented objects, as well as a perceptual evaluating of the scenes. A setup utilizing different lighting conditions is created. Different parameters affecting the realism are evaluated. These are camera artefacts, shadows, nu...

  6. MDCT angiography with 3D image reconstructions in the evaluation of failing arteriovenous fistulas and grafts in hemodialysis patients

    Dimopoulou, Angeliki; Raland, Hans; Magnusson, Anders (Dept. of Radiology, Univ. Hospital, Uppsala (Sweden)), email: angeliki.dimopoulou@akademiska.se; Wikstroem, Bjoern (Dept. of Medical Sciences, Renal Section, Univ. Hospital, Uppsala (Sweden))

    2011-11-15

    Background. Arteriovenous fistulas and grafts are the methods of choice for vascular access in renal failure patients in need of hemodialysis. Their major complication, however, is stenosis, which might lead to thrombosis. Purpose. To demonstrate the usefulness of 16-MDCTA with 3D image reconstructions, in long-term hemodialysis patients with dysfunctional arteriovenous fistulas and grafts (AVF and AVG). Material and Methods. During a 17-month period, 31 patients with dysfunctional AVF and AVG (24 AVF and seven AVG) were examined with MDCTA with 3D image postprocessing. Parameters such as comprehension of the anatomy, quality of contrast enhancement, and pathological vascular changes were measured. DSA was then performed in 24 patients. Results. MDCTA illustrated the anatomy of the AVF/AVG and the entire vascular tree to the heart, in a detailed and comprehensive manner in 93.5% of the evaluated segments, and depicted pathology of AVF/AVG or pathology of the associated vasculature. MDCTA demonstrated a total of 38 significant stenoses in 25 patients. DSA verified 37 stenoses in 24 patients and demonstrated two additional stenoses. MDCTA had thus a sensitivity of 95%. All 24 patients were treated with percutaneous transluminal angioplasty (PTA) with good technical results. Conclusion. MDCTA with 3D reconstructions of dysfunctioning AVFs and AVGs in hemodialysis patients is an accurate and reliable diagnostic method helping customize future intervention

  7. Metrics for evaluating 3D medical image segmentation: analysis, selection, and tool

    Taha, Abdel Aziz; Hanbury, Allan

    2015-01-01

    Background Medical Image segmentation is an important image processing step. Comparing images to evaluate the quality of segmentation is an essential part of measuring progress in this research area. Some of the challenges in evaluating medical segmentation are: metric selection, the use in the literature of multiple definitions for certain metrics, inefficiency of the metric calculation implementations leading to difficulties with large volumes, and lack of support for fuzzy segmentation by ...

  8. EVALUATION OF THE LIVER METASTASIS BY 3D-COMPUTED TOMOGRAPHY

    Iuliana Eva; R.C. Tiutiuca

    2005-01-01

    Abdominal spiral computed tomography is the method of choice for the diagnosis of hepatic metastasis, evaluating lesions even under 10 mm. Treatment depends of the hepatic and extrahepatic spread of disease. Therapeutical options include surgical ablation (resection, enucleation, crioablation, radiofrequency, liver transplant) or non-surgical (embolization or chemoembolization, therapeutic aproach through the hepatic artery). Precise diagnostic and evaluation of the extension of the disease...

  9. Evaluating the Potential of Rtk-Uav for Automatic Point Cloud Generation in 3d Rapid Mapping

    Fazeli, H.; Samadzadegan, F.; Dadrasjavan, F.

    2016-06-01

    During disaster and emergency situations, 3D geospatial data can provide essential information for decision support systems. The utilization of geospatial data using digital surface models as a basic reference is mandatory to provide accurate quick emergency response in so called rapid mapping activities. The recipe between accuracy requirements and time restriction is considered critical in this situations. UAVs as alternative platforms for 3D point cloud acquisition offer potentials because of their flexibility and practicability combined with low cost implementations. Moreover, the high resolution data collected from UAV platforms have the capabilities to provide a quick overview of the disaster area. The target of this paper is to experiment and to evaluate a low-cost system for generation of point clouds using imagery collected from a low altitude small autonomous UAV equipped with customized single frequency RTK module. The customized multi-rotor platform is used in this study. Moreover, electronic hardware is used to simplify user interaction with the UAV as RTK-GPS/Camera synchronization, and beside the synchronization, lever arm calibration is done. The platform is equipped with a Sony NEX-5N, 16.1-megapixel camera as imaging sensor. The lens attached to camera is ZEISS optics, prime lens with F1.8 maximum aperture and 24 mm focal length to deliver outstanding images. All necessary calibrations are performed and flight is implemented over the area of interest at flight height of 120 m above the ground level resulted in 2.38 cm GSD. Earlier to image acquisition, 12 signalized GCPs and 20 check points were distributed in the study area and measured with dualfrequency GPS via RTK technique with horizontal accuracy of σ = 1.5 cm and vertical accuracy of σ = 2.3 cm. results of direct georeferencing are compared to these points and experimental results show that decimeter accuracy level for 3D points cloud with proposed system is achievable, that is suitable

  10. Evaluation of Binocular Vision Therapy Efficacy by 3D Video-Oculography Measurement of Binocular Alignment and Motility

    Laria Ochaíta, Carlos; Piñero Llorens, David Pablo

    2013-01-01

    Objective: To evaluate two cases of intermittent exotropia (IX(T)) treated by vision therapy the efficacy of the treatment by complementing the clinical examination with a 3-D video-oculography to register and to evidence the potential applicability of this technology for such purpose. Methods: We report the binocular alignment changes occurring after vision therapy in a woman of 36 years with an IX(T) of 25 prism diopters (Δ) at far and 18 Δ at near and a child of 10 years with 8 Δ of IX(T) ...

  11. Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera.

    Chiabrando, Filiberto; Chiabrando, Roberto; Piatti, Dario; Rinaudo, Fulvio

    2009-01-01

    3D imaging with Time-of-Flight (ToF) cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR)-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.

  12. Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera

    Fulvio Rinaudo

    2009-12-01

    Full Text Available 3D imaging with Time-of-Flight (ToF cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.

  13. Radiochromic 3D Detectors

    Oldham, Mark

    2015-01-01

    Radiochromic materials exhibit a colour change when exposed to ionising radiation. Radiochromic film has been used for clinical dosimetry for many years and increasingly so recently, as films of higher sensitivities have become available. The two principle advantages of radiochromic dosimetry include greater tissue equivalence (radiologically) and the lack of requirement for development of the colour change. In a radiochromic material, the colour change arises direct from ionising interactions affecting dye molecules, without requiring any latent chemical, optical or thermal development, with important implications for increased accuracy and convenience. It is only relatively recently however, that 3D radiochromic dosimetry has become possible. In this article we review recent developments and the current state-of-the-art of 3D radiochromic dosimetry, and the potential for a more comprehensive solution for the verification of complex radiation therapy treatments, and 3D dose measurement in general.

  14. Evaluation of a Backpack-Mounted 3D Mobile Scanning System

    Helge A. Lauterbach

    2015-10-01

    Full Text Available Recently, several backpack-mounted systems, also known as personal laser scanning systems, have been developed. They consist of laser scanners or cameras that are carried by a human operator to acquire measurements of the environment while walking. These systems were first designed to overcome the challenges of mapping indoor environments with doors and stairs. While the human operator inherently has the ability to open doors and to climb stairs, the flexible movements introduce irregularities of the trajectory to the system. To compete with other mapping systems, the accuracy of these systems has to be evaluated. In this paper, we present an extensive evaluation of our backpack mobile mapping system in indoor environments. It is shown that the system can deal with the normal human walking motion, but has problems with irregular jittering. Moreover, we demonstrate the applicability of the backpack in a suitable urban scenario.

  15. 3D GIS BASED EVALUATION OF THE AVAILABLE SIGHT DISTANCE TO ASSESS SAFETY OF URBAN ROADS

    Bassani, M.; Grasso, N.; Piras, M.

    2015-01-01

    The available sight distance (ASD) in front of the driver to detect possible conflicts with unexpected obstacles is fundamental for traffic safety. In the last 20 years, road design software (RDS) has been continuously updated with dedicated modules to estimate ASD, thus assessing the quality of project from a safety point of view. Unfortunately, the evaluation of ASD still represents an issue in the case of existing road, and the object of discussion in the research community. To avoid probl...

  16. 3-D finite element stress analysis for fatigue design and evaluation: a parametric study of MOV(Motor Operated Valve)

    Kim, Hyeong Keun; Lee, Sang Min; Chang, Yoon Suk; Choi, Jae Boong; Kim, Young Jin [Sungkyunkwan Univ., Suwon (Korea, Republic of); Kim, Yun Jae [Korea Univ., Seoul (Korea, Republic of)

    2004-07-01

    In this paper, a new procedure is proposed to accomplish the primary plus secondary stress(P+Q) at the 'structural element' instead of 'transition element'. For the P+Q evaluation, the calculated stresses by FEA are linearized along a stress classification line to extract the stress category, then the stress intensity is calculated to compare with the 3Sm limit. Also, in this paper, the 'design by analysis' criteria, adopted fundamental concepts and a new approach to calculate Ke factors are explained. The new procedure combined with 3-D FEA has been applied to motor operated valve in order to the over conservatism and the rack of margin. The evaluation results show a good applicability and can be utilized for fatigue life evaluation by using P+Q.

  17. 3D GIS BASED EVALUATION OF THE AVAILABLE SIGHT DISTANCE TO ASSESS SAFETY OF URBAN ROADS

    M. Bassani

    2015-08-01

    Full Text Available The available sight distance (ASD in front of the driver to detect possible conflicts with unexpected obstacles is fundamental for traffic safety. In the last 20 years, road design software (RDS has been continuously updated with dedicated modules to estimate ASD, thus assessing the quality of project from a safety point of view. Unfortunately, the evaluation of ASD still represents an issue in the case of existing road, and the object of discussion in the research community. To avoid problems related to the limitation associated with the use of digital terrain models typically employed in RDS, the Geographic Information Systems (GIS software can use digital surface models (DSM which are more flexible in the modelling of sight obstruction due to vegetation, street furniture, and vertical surfaces largely diffused in urbanized areas. The paper deals with the evaluation of GIS in the estimation of ASD in a typical urban road where the density of sight obstruction along the roadside is relatively high. The work explores the case study of a collector road in the city of Turin (Italy. Results confirm the potentiality of GIS software in capturing the complex morphology of the urban environment, thus confirming that GIS could become an important analysis tool for road engineers in the field of road safety. The investigation here described is part of the Pro-VISION Project (funded in 2014 by the Regione Piemonte, Italy.

  18. 3D computed tomographic evaluation of secondary alveolar bone grafts in cleft lip and palate patients

    Ohkubo, Fumio; Akai, Hidemi; Hosaka, Yoshiaki [Showa Univ., Tokyo (Japan). School of Medicine

    2001-04-01

    Alveolar bone grafting in patients with cleft lip and palate has becomes a routine part of most treatment regimes. This study was undertaken to estimate how much bone needs to be grafted into the cleft cavity and to evaluate the grafted bone using 3-DCT over a period from the early postoperative stage to after one year. Seventy-five patients divided into four groups according to the type of cleft were studied. All patients underwent secondary alveolar bone grafting using particulate cancellous bone from the anterior iliac crest. The bone graft areas were divided into two regions: the extra-cleft region and the intra-cleft region. The weight and the volume of the grafted bone were correlated and the average density was 1.5 g/ml regardless of the cleft type. The bone in the extra-cleft region could be seen in almost all slices of the CT scans, from the lower alveolar process to the piriform aperture. The extra-cleft graft ratio of unilateral and bilateral cleft lip and palate is higher than that of cleft lip and alveolus. The extra-cleft grafting is necessary to restore facial symmetry. The grafted bone was decreased in both height and volume following three months and adequate bone bridging was maintained for one year. We concluded that 3-DCT findings are one of the most valuable methods to evaluate postoperative conditions after alveolar bone grafting. (author)

  19. Segmentation Based Classification of 3D Urban Point Clouds: A Super-Voxel Based Approach with Evaluation

    Laurent Trassoudaine

    2013-03-01

    Full Text Available Segmentation and classification of urban range data into different object classes have several challenges due to certain properties of the data, such as density variation, inconsistencies due to missing data and the large data size that require heavy computation and large memory. A method to classify urban scenes based on a super-voxel segmentation of sparse 3D data obtained from LiDAR sensors is presented. The 3D point cloud is first segmented into voxels, which are then characterized by several attributes transforming them into super-voxels. These are joined together by using a link-chain method rather than the usual region growing algorithm to create objects. These objects are then classified using geometrical models and local descriptors. In order to evaluate the results, a new metric that combines both segmentation and classification results simultaneously is presented. The effects of voxel size and incorporation of RGB color and laser reflectance intensity on the classification results are also discussed. The method is evaluated on standard data sets using different metrics to demonstrate its efficacy.

  20. 3-D VARIABLE PARAMETER NUMERICAL MODEL FOR EVALUATION OF THE PLANNED EXPLOITABLE GROUNDWATER RESOURCE IN REGIONAL UNCONSOLIDATED SEDIMENTS

    LUO Zu-jiang; WANG Yan

    2012-01-01

    In order to correctly evaluate the exploitable groundwater resource in regional complex,thick Quaternary unconsolidated sediments,the whole Quaternary unconsolidated sediments are considered as a unified hydrogeological unit and a 3-D unsteady groundwater flow numerical model is adopted.Meanwhile,with the consideration of the dynamic changes of the porosity,the hydraulic conductivity and the specific storage with the groundwater level dropping during the exploitation process,an improved composite element seepage matrix adjustment method is applied to solve the unsteady flow problem of free surface.In order to evaluate the exploitable groundwater resource in Cangzhou,Hebei Province,the hydrogeological conceptual model of Cangzhou is generalized to establish,a 3-D variable parameter numerical model of Cangzhou.Based on the prediction of the present groundwater exploitation,and by adjusting the groundwater exploitation layout,the exploitable groundwater resource is predicted.The model enjoys features like good convergence,good stability and high precision.

  1. Micro-computed tomography image-based evaluation of 3D anisotropy degree of polymer scaffolds.

    Pérez-Ramírez, Ursula; López-Orive, Jesús Javier; Arana, Estanislao; Salmerón-Sánchez, Manuel; Moratal, David

    2015-01-01

    Anisotropy is one of the most meaningful determinants of biomechanical behaviour. This study employs micro-computed tomography (μCT) and image techniques for analysing the anisotropy of regenerative medicine polymer scaffolds. For this purpose, three three-dimensional anisotropy evaluation image methods were used: ellipsoid of inertia (EI), mean intercept length (MIL) and tensor scale (t-scale). These were applied to three patterns (a sphere, a cube and a right prism) and to two polymer scaffold topologies (cylindrical orthogonal pore mesh and spherical pores). For the patterns, the three methods provided good results. Regarding the scaffolds, EI mistook both topologies (0.0158, [-0.5683; 0.6001]; mean difference and 95% confidence interval), and MIL showed no significant differences (0.3509, [0.0656; 0.6362]). T-scale is the preferable method because it gave the best capability (0.3441, [0.1779; 0.5102]) to differentiate both topologies. This methodology results in the development of non-destructive tools to engineer biomimetic scaffolds, incorporating anisotropy as a fundamental property to be mimicked from the original tissue and permitting its assessment by means of μCT image analysis.

  2. Development and Evaluation of a UAV-Photogrammetry System for Precise 3D Environmental Modeling

    Mozhdeh Shahbazi

    2015-10-01

    Full Text Available The specific requirements of UAV-photogrammetry necessitate particular solutions for system development, which have mostly been ignored or not assessed adequately in recent studies. Accordingly, this paper presents the methodological and experimental aspects of correctly implementing a UAV-photogrammetry system. The hardware of the system consists of an electric-powered helicopter, a high-resolution digital camera and an inertial navigation system. The software of the system includes the in-house programs specifically designed for camera calibration, platform calibration, system integration, on-board data acquisition, flight planning and on-the-job self-calibration. The detailed features of the system are discussed, and solutions are proposed in order to enhance the system and its photogrammetric outputs. The developed system is extensively tested for precise modeling of the challenging environment of an open-pit gravel mine. The accuracy of the results is evaluated under various mapping conditions, including direct georeferencing and indirect georeferencing with different numbers, distributions and types of ground control points. Additionally, the effects of imaging configuration and network stability on modeling accuracy are assessed. The experiments demonstrated that 1.55 m horizontal and 3.16 m vertical absolute modeling accuracy could be achieved via direct geo-referencing, which was improved to 0.4 cm and 1.7 cm after indirect geo-referencing.

  3. Development and Evaluation of a UAV-Photogrammetry System for Precise 3D Environmental Modeling

    Shahbazi, Mozhdeh; Sohn, Gunho; Théau, Jérôme; Menard, Patrick

    2015-01-01

    The specific requirements of UAV-photogrammetry necessitate particular solutions for system development, which have mostly been ignored or not assessed adequately in recent studies. Accordingly, this paper presents the methodological and experimental aspects of correctly implementing a UAV-photogrammetry system. The hardware of the system consists of an electric-powered helicopter, a high-resolution digital camera and an inertial navigation system. The software of the system includes the in-house programs specifically designed for camera calibration, platform calibration, system integration, on-board data acquisition, flight planning and on-the-job self-calibration. The detailed features of the system are discussed, and solutions are proposed in order to enhance the system and its photogrammetric outputs. The developed system is extensively tested for precise modeling of the challenging environment of an open-pit gravel mine. The accuracy of the results is evaluated under various mapping conditions, including direct georeferencing and indirect georeferencing with different numbers, distributions and types of ground control points. Additionally, the effects of imaging configuration and network stability on modeling accuracy are assessed. The experiments demonstrated that 1.55 m horizontal and 3.16 m vertical absolute modeling accuracy could be achieved via direct geo-referencing, which was improved to 0.4 cm and 1.7 cm after indirect geo-referencing. PMID:26528976

  4. Development and Evaluation of a UAV-Photogrammetry System for Precise 3D Environmental Modeling.

    Shahbazi, Mozhdeh; Sohn, Gunho; Théau, Jérôme; Menard, Patrick

    2015-10-30

    The specific requirements of UAV-photogrammetry necessitate particular solutions for system development, which have mostly been ignored or not assessed adequately in recent studies. Accordingly, this paper presents the methodological and experimental aspects of correctly implementing a UAV-photogrammetry system. The hardware of the system consists of an electric-powered helicopter, a high-resolution digital camera and an inertial navigation system. The software of the system includes the in-house programs specifically designed for camera calibration, platform calibration, system integration, on-board data acquisition, flight planning and on-the-job self-calibration. The detailed features of the system are discussed, and solutions are proposed in order to enhance the system and its photogrammetric outputs. The developed system is extensively tested for precise modeling of the challenging environment of an open-pit gravel mine. The accuracy of the results is evaluated under various mapping conditions, including direct georeferencing and indirect georeferencing with different numbers, distributions and types of ground control points. Additionally, the effects of imaging configuration and network stability on modeling accuracy are assessed. The experiments demonstrated that 1.55 m horizontal and 3.16 m vertical absolute modeling accuracy could be achieved via direct geo-referencing, which was improved to 0.4 cm and 1.7 cm after indirect geo-referencing.

  5. Combining 3D human in vitro methods for a 3Rs evaluation of novel titanium surfaces in orthopaedic applications

    Stevenson, G.; Rehman, S.; Draper, E.; Hernández‐Nava, E.; Hunt, J.

    2016-01-01

    ABSTRACT In this study, we report on a group of complementary human osteoblast in vitro test methods for the preclinical evaluation of 3D porous titanium surfaces. The surfaces were prepared by additive manufacturing (electron beam melting [EBM]) and plasma spraying, allowing the creation of complex lattice surface geometries. Physical properties of the surfaces were characterized by SEM and profilometry and 3D in vitro cell culture using human osteoblasts. Primary human osteoblast cells were found to elicit greater differences between titanium sample surfaces than an MG63 osteoblast‐like cell line, particularly in terms of cell survival. Surface morphology was associated with higher osteoblast metabolic activity and mineralization on rougher titanium plasma spray coated surfaces than smoother surfaces. Differences in osteoblast survival and metabolic activity on titanium lattice structures were also found, despite analogous surface morphology at the cellular level. 3D confocal microscopy identified osteoblast organization within complex titanium surface geometries, adhesion, spreading, and alignment to the biomaterial strut geometries. Mineralized nodule formation throughout the lattice structures was also observed, and indicative of early markers of bone in‐growth on such materials. Testing methods such as those presented are not traditionally considered by medical device manufacturers, but we suggest have value as an increasingly vital tool in efficiently translating pre‐clinical studies, especially in balance with current regulatory practice, commercial demands, the 3Rs, and the relative merits of in vitro and in vivo studies. Biotechnol. Bioeng. 2016;113: 1586–1599. © 2015 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. PMID:26702609

  6. Qualification of coupled 3D neutron kinetic/thermal hydraulic code systems by the calculation of a VVER-440 benchmark. Re-connection of an isolated loop

    Kotsarev, Alexander; Lizorkin, Mikhail [National Research Centre ' Kurchatov Institute' , Moscow (Russian Federation); Bencik, Marek; Hadek, Jan [UJV Rez, a.s., Rez (Czech Republic); Kozmenkov, Yaroslav; Kliem, Soeren [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany)

    2016-09-15

    The 7th AER dynamic benchmark is a continuation of the efforts to validate the codes systematically for the estimation of the transient behavior of VVER type nuclear power plants. The main part of the benchmark is the simulation of the re-connection of an isolated circulation loop with low temperature in a VVER-440 plant. This benchmark was calculated by the National Research Centre ''Kurchatov Institute'' (with the code ATHLET/BIPR-VVER), UJV Rez (with the code RELAP5-3D {sup copyright}) and HZDR (with the code DYN3D/ATHLET). The paper gives an overview of the behavior of the main thermal hydraulic and neutron kinetic parameters in the provided solutions.

  7. Positional precision evaluation of 3 D laser scanner based on 3 D control field%基于三维控制场的三维激光扫描仪点位精度评定

    史波; 郑敏

    2015-01-01

    为评定三维激光扫描仪的精度,设计了一个基于室内三维控制场的RIEGL VZ-400点位精度评定方案。通过实测得到其在距离10 m左右的外部、内部符合精度分别为±1.675 mm和±0.48 mm。详细介绍了室内全景三维控制场的布设、数据采集以及点位精度的评定方法。研究结果可为地面三维激光扫描仪的工程应用提供精度依据。%For evaluating the precision of a 3D laser scanner, we designed a positional precision evaluation solution for RIEGL VZ-400 on the basis of the 3D indoor panoramic control field. Through the evaluation, the precision of external and internal po-sition at distance of 10 m is ± 1. 675mm and ± 0. 48mm respectively. The layout, data collection way and the positional preci-sion evaluation method are introduced. The results could provide experiences and references for the application of ground 3D laser scanners.

  8. Research and Teaching: Methods for Creating and Evaluating 3D Tactile Images to Teach STEM Courses to the Visually Impaired

    Hasper, Eric; Windhorst, Rogier; Hedgpeth, Terri; Van Tuyl, Leanne; Gonzales, Ashleigh; Martinez, Britta; Yu, Hongyu; Farkas, Zolton; Baluch, Debra P.

    2015-01-01

    Project 3D IMAGINE or 3D Image Arrays to Graphically Implement New Education is a pilot study that researches the effectiveness of incorporating 3D tactile images, which are critical for learning science, technology, engineering, and mathematics, into entry-level lab courses. The focus of this project is to increase the participation and…

  9. Synthesis, biological evaluation and 3D-QSAR studies of new chalcone derivatives as inhibitors of human P-glycoprotein.

    Parveen, Zahida; Brunhofer, Gerda; Jabeen, Ishrat; Erker, Thomas; Chiba, Peter; Ecker, Gerhard F

    2014-04-01

    P-glycoprotein (P-gp) is an ATP-dependent multidrug resistance efflux transporter that plays an important role in anticancer drug resistance and in pharmacokinetics of medicines. Despite a large number of structurally and functionally diverse compounds, also flavonoids and chalcones have been reported as inhibitors of P-gp. The latter share some similarity with the well studied class of propafenones, but do not contain a basic nitrogen atom. Furthermore, due to their rigidity, they are suitable candidates for 3D-QSAR studies. In this study, a set of 22 new chalcone derivatives were synthesized and evaluated in a daunomycin efflux inhibition assay using the CCRF.CEM.VCR1000 cell line. The compound 10 showed the highest activity (IC50=42nM), which is one order of magnitude higher than the activity for an equilipohillic propafenone analogue. 2D- and 3D-QSAR studies indicate the importance of H-bond acceptors, methoxy groups, hydrophobic groups as well as the number of rotatable bonds as pharmacophoric features influencing P-gp inhibitory activity.

  10. Extraction of 3D Femur Neck Trabecular Bone Architecture from Clinical CT Images in Osteoporotic Evaluation: a Novel Framework.

    Sapthagirivasan, V; Anburajan, M; Janarthanam, S

    2015-08-01

    The early detection of osteoporosis risk enhances the lifespan and quality of life of an individual. A reasonable in-vivo assessment of trabecular bone strength at the proximal femur helps to evaluate the fracture risk and henceforth, to understand the associated structural dynamics on occurrence of osteoporosis. The main aim of our study was to develop a framework to automatically determine the trabecular bone strength from clinical femur CT images and thereby to estimate its correlation with BMD. All the 50 studied south Indian female subjects aged 30 to 80 years underwent CT and DXA measurements at right femur region. Initially, the original CT slices were intensified and active contour model was utilised for the extraction of the neck region. After processing through a novel process called trabecular enrichment approach (TEA), the three dimensional (3D) trabecular features were extracted. The extracted 3D trabecular features, such as volume fraction (VF), solidity of delta points (SDP) and boundness, demonstrated a significant correlation with femoral neck bone mineral density (r = 0.551, r = 0.432, r = 0.552 respectively) at p TEA method would be useful for spotting women vulnerable to osteoporotic risk.

  11. Evaluation of 3D pre-treatment verification for volumetric modulated arc therapy plan in head region

    Ruangchan, S.; Oonsiri, S.; Suriyapee, S.

    2016-03-01

    The development of pre-treatment QA tools contributes to the three dimension (3D) dose verification using the calculation software with the measured planar dose distribution. This research is aimed to evaluate the Sun Nuclear 3DVH software with Thermo luminescence dosimeter (TLD) measurement. The two VMAT patient plans (2.5 arcs) of 6 MV photons with different PTV locations were transferred to the Rando phantom images. The PTV of the first plan located in homogeneous area and vice versa in the second plan. For treatment planning process, the Rando phantom images were employed in optimization and calculation with the PTV, brain stem, lens and TLD position contouring. The verification plans were created, transferred to the ArcCHECK for measurement and calculated the 3D dose using 3DVH software. The range of the percent dose differences in both PTV and organ at risk (OAR) between TLD and 3DVH software of the first and the second plans were -2.09 to 3.87% and -1.39 to 6.88%, respectively. The mean percent dose differences for the PTV were 1.62% and 3.93% for the first and the second plans, respectively. In conclusion, the 3DVH software results show good agreement with TLD when the tumor located in the homogeneous area.

  12. Quantitative Evaluation of Tissue Surface Adaption of CAD-Designed and 3D Printed Wax Pattern of Maxillary Complete Denture

    Hu Chen

    2015-01-01

    Full Text Available Objective. To quantitatively evaluate the tissue surface adaption of a maxillary complete denture wax pattern produced by CAD and 3DP. Methods. A standard edentulous maxilla plaster cast model was used, for which a wax pattern of complete denture was designed using CAD software developed in our previous study and printed using a 3D wax printer, while another wax pattern was manufactured by the traditional manual method. The cast model and the two wax patterns were scanned in the 3D scanner as “DataModel,” “DataWaxRP,” and “DataWaxManual.” After setting each wax pattern on the plaster cast, the whole model was scanned for registration. After registration, the deviations of tissue surface between “DataModel” and “DataWaxRP” and between “DataModel” and “DataWaxManual” were measured. The data was analyzed by paired t-test. Results. For both wax patterns produced by the CAD&RP method and the manual method, scanning data of tissue surface and cast surface showed a good fit in the majority. No statistically significant (P>0.05 difference was observed between the CAD&RP method and the manual method. Conclusions. Wax pattern of maxillary complete denture produced by the CAD&3DP method is comparable with traditional manual method in the adaption to the edentulous cast model.

  13. Shaping 3-D boxes

    Stenholt, Rasmus; Madsen, Claus B.

    2011-01-01

    Enabling users to shape 3-D boxes in immersive virtual environments is a non-trivial problem. In this paper, a new family of techniques for creating rectangular boxes of arbitrary position, orientation, and size is presented and evaluated. These new techniques are based solely on position data...

  14. Evaluating integration of inland bathymetry in the U.S. Geological Survey 3D Elevation Program, 2014

    Miller-Corbett, Cynthia

    2016-09-01

    Inland bathymetry survey collections, survey data types, features, sources, availability, and the effort required to integrate inland bathymetric data into the U.S. Geological Survey 3D Elevation Program are assessed to help determine the feasibility of integrating three-dimensional water feature elevation data into The National Map. Available data from wading, acoustic, light detection and ranging, and combined technique surveys are provided by the U.S. Geological Survey, National Oceanic and Atmospheric Administration, U.S. Army Corps of Engineers, and other sources. Inland bathymetric data accessed through Web-hosted resources or contacts provide useful baseline parameters for evaluating survey types and techniques used for collection and processing, and serve as a basis for comparing survey methods and the quality of results. Historically, boat-mounted acoustic surveys have provided most inland bathymetry data. Light detection and ranging techniques that are beneficial in areas hard to reach by boat, that can collect dense data in shallow water to provide comprehensive coverage, and that can be cost effective for surveying large areas with good water clarity are becoming more common; however, optimal conditions and techniques for collecting and processing light detection and ranging inland bathymetry surveys are not yet well defined.Assessment of site condition parameters important for understanding inland bathymetry survey issues and results, and an evaluation of existing inland bathymetry survey coverage are proposed as steps to develop criteria for implementing a useful and successful inland bathymetry survey plan in the 3D Elevation Program. These survey parameters would also serve as input for an inland bathymetry survey data baseline. Integration and interpolation techniques are important factors to consider in developing a robust plan; however, available survey data are usually in a triangulated irregular network format or other format compatible with

  15. Probabilistic thermal-mechanical fatigue criterion for lost foam casting aluminium alloys based on 2D/3D porosities distribution

    Szmytka F.; Limodin N.; Wang L; Osmond P.; Adrien J.; Charkaluk E.; Buffiere J.Y.

    2014-01-01

    A thermal-mechanical fatigue criterion is proposed to assess the lifetime of aluminium alloys produced by a lost foam casting process. It is based on the observed size distribution of pores sizes which are considered as critical zones for cracks initiation and gives reliable results when both pores sizes are identified from X-ray tomography and mean stresses are taken into account. Lifetime probabilities are finally successfully compared with experimental results.

  16. Probabilistic thermal-mechanical fatigue criterion for lost foam casting aluminium alloys based on 2D/3D porosities distribution

    Szmytka F.

    2014-06-01

    Full Text Available A thermal-mechanical fatigue criterion is proposed to assess the lifetime of aluminium alloys produced by a lost foam casting process. It is based on the observed size distribution of pores sizes which are considered as critical zones for cracks initiation and gives reliable results when both pores sizes are identified from X-ray tomography and mean stresses are taken into account. Lifetime probabilities are finally successfully compared with experimental results.

  17. On the Analysis and Evaluation of Direct Containement Heating with the Multidimensional Multiphase Flow Code MC3D

    Tanguy Janin

    2010-01-01

    Full Text Available In the course of a postulated severe accident in an NPP, Direct Containment Heating (DCH may occur after an eventual failure of the vessel. DCH is related to dynamical, thermal, and chemical phenomena involved by the eventual fine fragmentation and dispersal of the corium melt out of the vessel pit. It may threaten the integrity of the containment by pressurization of its atmosphere. Several simplified modellings have been proposed in the past but they require a very strong fitting which renders any extrapolation regarding geometry, material, and scales rather doubtful. With the development of multidimensional multiphase flow computer codes, it is now possible to investigate the phenomenon numerically with more details. We present an analysis of the potential of the MC3D code to support the analysis of this phenomenon, restricting our discussion to the dynamical processes. The analysis is applied to the case of French 1300 MWe PWR reactors for which we derive a correlation for the corium dispersal rate for application in a Probabilistic Safety Analysis (PSA level 2 study.

  18. Research on the aero-thermal effects by 3D analysis model of the optical window of the infrared imaging guidance

    Xu, Bo; Li, Lin; Zhu, Ying

    2014-11-01

    Researches on hypersonic vehicles have been a hotspot in the field of aerospace because of the pursuits for higher speed by human being. Infrared imaging guidance is playing a very important role in modern warfare. When an Infrared Ray(IR) imaging guided missile is flying in the air at high speed, its optical dome suffers from serious aero-optic effects because of air flow. The turbulence around the dome and the thermal effects of the optical window would cause disturbance to the wavefront from the target. Therefore, detected images will be biased, dithered and blurred, and the capabilities of the seeker for detecting, tracking and recognizing are weakened. In this paper, methods for thermal and structural analysis with Heat Transfer and Elastic Mechanics are introduced. By studying the aero-thermal effects and aero-thermal radiation effects of the optical window, a 3D analysis model of the optical window is established by using finite element method. The direct coupling analysis is employed as a solving strategy. The variation regularity of the temperature field is obtained. For light with different incident angles, the influence on the ray propagation caused by window deformation is analyzed with theoretical calculation and optical/thermal/structural integrated analysis method respectively.

  19. 3D features of delayed thermal convection in fault zones: consequences for deep fluid processes in the Tiberias Basin, Jordan Rift Valley

    Magri, Fabien; Möller, Sebastian; Inbar, Nimrod; Siebert, Christian; Möller, Peter; Rosenthal, Eliyahu; Kühn, Michael

    2015-04-01

    It has been shown that thermal convection in faults can also occur for subcritical Rayleigh conditions. This type of convection develops after a certain period and is referred to as "delayed convection" (Murphy, 1979). The delay in the onset is due to the heat exchange between the damage zone and the surrounding units that adds a thermal buffer along the fault walls. Few numerical studies investigated delayed thermal convection in fractured zones, despite it has the potential to transport energy and minerals over large spatial scales (Tournier, 2000). Here 3D numerical simulations of thermally driven flow in faults are presented in order to investigate the impact of delayed convection on deep fluid processes at basin-scale. The Tiberias Basin (TB), in the Jordan Rift Valley, serves as study area. The TB is characterized by upsurge of deep-seated hot waters along the faulted shores of Lake Tiberias and high temperature gradient that can locally reach 46 °C/km, as in the Lower Yarmouk Gorge (LYG). 3D simulations show that buoyant flow ascend in permeable faults which hydraulic conductivity is estimated to vary between 30 m/yr and 140 m/yr. Delayed convection starts respectively at 46 and 200 kyrs and generate temperature anomalies in agreement with observations. It turned out that delayed convective cells are transient. Cellular patterns that initially develop in permeable units surrounding the faults can trigger convection also within the fault plane. The combination of these two convective modes lead to helicoidal-like flow patterns. This complex flow can explain the location of springs along different fault traces of the TB. Besides being of importance for understanding the hydrogeological processes of the TB (Magri et al., 2015), the presented simulations provide a scenario illustrating fault-induced 3D cells that could develop in any geothermal system. References Magri, F., Inbar, N., Siebert, C., Rosenthal, E., Guttman, J., Möller, P., 2015. Transient

  20. The Role and Practice of Property Optimisation to Help Evaluate 3D Geological Models using Gravity and Magnetic Data

    Lane, R.

    2008-12-01

    As the shift from 2D to 3D geological mapping gathers strength and the number of multi-component potential field data sets increases, there is a need for greater sophistication in the gravity and magnetic modelling tools that can be used to help evaluate and refine the properties and geometry of the various units within these models. The hitherto standard approach of 2D forward modelling of selected cross-sections is progressively giving way to full 3D forward modelling. An example of a user-guided optimisation method to streamline what would otherwise be a time-consuming and frustrating manual iterative refinement process in 3D is presented. A combination of the density and magnetic properties assigned to each geological unit is derived such that the total calculated response best matches the supplied scalar, vector or tensor gravity and magnetic field observations, subject to specified levels of uncertainty (bounds) in the properties. Numerical optimisation is achieved with a standard linear least squares routine, subject to equality and bounds constraints. The user is presented with 3 standard options for every property, allowing the property values to be either (a) fixed, (b) free to vary within a specified range, or (c) free vary over a very broad range. Additionally, properties for a group of geological units can be linked so that they all return the same value. The parameterisation of density properties is relatively straight forward with a single property for each geological unit. Magnetic properties present more of a challenge. Three distinct scenarios are identified and a separate option can be selected for each geological unit. These assume (1) only induced susceptibility, (2) a combination of induced susceptibility and remanent magnetisation of know direction, or (3) a combination of induced susceptibility and remanent magnetisation of unknown direction. In this latter case, a solution is obtained for the total effective magnetisation in the form of 3

  1. Spatial and Temporal Variability in the Circulation and Thermal Evolution of the Mantle in Subduction Zones: Insights From 3-D Laboratory Experiments.

    Kincaid, C.; Griffiths, R. W.

    2003-12-01

    The subduction of oceanic lithosphere plays a key role in plate tectonics, the thermal evolution of the mantle and recycling processes between Earth's interior and surface. The majority of subduction models are two-dimensional (2-D), assuming limited variability in the direction parallel to the trench. Observationally based models increasingly appeal to three-dimensional (3-D) flow associated with trench migration and the sinking of oceanic plates with a translational component of motion (rollback). We report results from laboratory experiments that reveal fundamental differences in 3-D mantle circulation and temperature structure in response to subduction with and without a rollback component. In our experiments the upper mantle is simulated with glucose syrup and the subducting plate is represented with a Phenolic sheet that is forced to sink into the glucose along prescribed trajectories. An array of 40 thermisters embedded within the plate is used to monitor slab surface temperatures (SSTs). We vary the relative magnitude of downdip and translational components of slab motion and also consider cases where the plate steepens with time. Another parameter is the initial thickness of the thermal boundary layer (TBL) beneath the overriding plate. Without rollback motion, flow in the mantle wedge is sluggish, there is no mass flux around the plate, and plate edges heat up faster than plate centers. Rollback subduction drives flow around and beneath the sinking plate, velocities increase within the mantle wedge and are focussed towards the center of the plate and the surface of the plate heats more along the centerline. In addition to lateral variability in flow and mantle temperatures, results highlight temporal variability in SSTs and 3-D mantle flow trajectories associated with the initiation of subduction and variations between periods of predominantly downdip versus rollback sinking.

  2. A zero-footprint 3D visualization system utilizing mobile display technology for timely evaluation of stroke patients

    Park, Young Woo; Guo, Bing; Mogensen, Monique; Wang, Kevin; Law, Meng; Liu, Brent

    2010-03-01

    When a patient is accepted in the emergency room suspected of stroke, time is of the utmost importance. The infarct brain area suffers irreparable damage as soon as three hours after the onset of stroke symptoms. A CT scan is one of standard first line of investigations with imaging and is crucial to identify and properly triage stroke cases. The availability of an expert Radiologist in the emergency environment to diagnose the stroke patient in a timely manner only increases the challenges within the clinical workflow. Therefore, a truly zero-footprint web-based system with powerful advanced visualization tools for volumetric imaging including 2D. MIP/MPR, 3D display can greatly facilitate this dynamic clinical workflow for stroke patients. Together with mobile technology, the proper visualization tools can be delivered at the point of decision anywhere and anytime. We will present a small pilot project to evaluate the use of mobile technologies using devices such as iPhones in evaluating stroke patients. The results of the evaluation as well as any challenges in setting up the system will also be discussed.

  3. Evaluation of the Heading Confinement Pressure Effect on Ground Settlement for EPBTBM Using Full 3D Numerical Analysis

    Amir Hossein Haghi

    2013-06-01

    Full Text Available Ground settlement is often the most serious concern when tunneling under an old city with numerous historic monuments. A successful engineering design under these conditions would require getting the most out of the ground strength parameters and avoiding any weakening maneuver throughout the operation. Knowing that surface settlement is highly affected by tunneling parameters in EPB shield tunneling lead us to estimate the optimum values for the machine heading pressure with the lower amount of the ground settlement in fragile structure of the old city for the Esfahan Subway Project. Tunnels were dug underneath some of the most prominent historical sites along the path of the project. To improve precision and efficiency in tunneling operation, at the first step, tunnel heading confinement pressure is calculated by using an advanced 3D mathematical approach based on the limit equilibrium theory. Then, a promoted 3D finite element model is developed, taking into account the tunneling procedures and the designed heading confinement pressure from the first step. Settlements were pre-calculated and the surface displacement was checked at all sensitive locations. At the third step, settlement is estimated by exerting executed face supporting pressure to the tunnel face and the concluded amounts for displacement are compared with the outputs of extensometers. This comparison leads us to check the reliability of calculated settlements and the accuracy of the designed tunnel heading confinement pressure. Furthermore, evaluating the relation between extensometer outputs and executed tunnel face pressure at the points of extensometers stations validates the assumption that the safe face supporting pressure causes least surface displacement. Although the minimum pressure occurred in short term fluctuations, this approach confirms the sensibility of settlement with the least executed face supporting pressure.. It is also found that higher executed face

  4. Toxicity evaluation of magnetic hyperthermia induced by remote actuation of magnetic nanoparticles in 3D micrometastasic tumor tissue analogs for triple negative breast cancer.

    Stocke, Nathanael A; Sethi, Pallavi; Jyoti, Amar; Chan, Ryan; Arnold, Susanne M; Hilt, J Zach; Upreti, Meenakshi

    2017-03-01

    Magnetic hyperthermia as a treatment modality is acquiring increased recognition for loco-regional therapy of primary and metastatic lung malignancies by pulmonary delivery of magnetic nanoparticles (MNP). The unique characteristic of magnetic nanoparticles to induce localized hyperthermia in the presence of an alternating magnetic field (AMF) allows for preferential killing of cells at the tumor site. In this study we demonstrate the effect of hyperthermia induced by low and high dose of MNP under the influence of an AMF using 3D tumor tissue analogs (TTA) representing the micrometastatic, perfusion independent stage of triple negative breast cancer (TNBC) that infiltrates the lungs. While application of inhalable magnetic nanocomposite microparticles or magnetic nanocomposites (MnMs) to the micrometastatic TNBC model comprised of TTA generated from cancer and stromal cells, showed no measureable adverse effects in the absence of AMF-exposure, magnetic hyperthermia generated under the influence of an AMF in TTA incubated in a high concentration of MNP (1 mg/mL) caused significant increase in cellular death/damage with mechanical disintegration and release of cell debris indicating the potential of these inhalable composites as a promising approach for thermal treatment of diseased lungs. The novelty and significance of this study lies in the development of methods to evaluate in vitro the application of inhalable composites containing MNPs in thermal therapy using a physiologically relevant metastatic TNBC model representative of the microenvironmental characteristics in secondary lung malignancies.

  5. Evaluation of a 3D system based on a high-quality flat screen and polarized glasses for use by surgical assistants during robotic surgery

    Kazushi Tanaka

    2014-01-01

    Full Text Available Introduction: One of the main benefits of robotic surgery is the surgeon′s three-dimensional (3D vision system. The purpose of this study is to evaluate the efficacy of 3D vision using a flat screen and polarized glasses for surgical skills during robotic surgeries. Materials and Methods: In an experimental model, six surgeons performed three surgical tasks with laparoscopic devices using a standard 2D and a flat-screen 3D model with polarized glasses. Performance times were compared between two-dimensional (2D and 3D vision for each task. The surgeons also graded the efficiency of the 3D system, on a subjective scale of 0-100. Results: Performance times for task 1 (seven holes and 2 (elastic bands were significantly reduced by 84% and 56% using 3D compared with a 2D system and experienced surgeons performed all three tasks faster in 3D than 2D. The surgeons reported the polarized glasses were comfortable to wear and direct vision was seldom affected. Conclusions: The use of 3D visualization seems to improve the efficiency of surgical skills during robotic surgery and reduce performance time for characteristic surgical procedure tasks.

  6. A Novel 3D Thermal Impedance Model for High Power Modules Considering Multi-layer Thermal Coupling and Different Heating/Cooling Conditions

    Bahman, Amir Sajjad; Ma, Ke; Blaabjerg, Frede

    2015-01-01

    Thermal management of power electronic devices is essential for reliable performance especially at high power levels. One of the most important activities in the thermal management and reliability improvement is acquiring the temperature information in critical points of the power module. However...... the multi-layer thermal coupling among chips is proposed. The impacts to the thermal impedance by various cooling and heating conditions are also studied. It is concluded that the heating and cooling conditions will have influence on the junction to case thermal impedances and need to be carefully...

  7. Constraints on the Lost City Hydrothermal System from borehole thermal data; 3-D models of heat flow and hydrothermal circulation in an oceanic core complex.

    Titarenko, S.; McCaig, A. M.

    2014-12-01

    A perennial problem in near-ridge hydrothermal circulation is that the only directly measurable data to test models is often vent fluid temperature. Surface heat flow measurements may be available but without the underlying thermal structure it is not known if they are transient and affected by local hydrothermal flow, or conductive. The Atlantis Massif oceanic core complex at 30 °N on the mid-Atlantic Ridge, offers a unique opportunity to better constrain hydrothermal circulation models. The temperature profile in gabbroic rocks of IODP Hole 1309D was measured in IODPExpedition 340T, and found to be near-conductive, but with a slight inflexion at ~750 mbsf indicating downward advection of fluid above that level. The lack of deep convection is especially remarkable given that the long-lived Lost City Hydrothermal Field (LCHF) is located only 5km to the south. We have modelled hydrothermal circulation in the Massif using Comsol Multiphysics, comparing 2-D and 3-D topographic models and using temperature-dependent conductivity to give the best estimate of heatflow into the Massif. We can constrain maximum permeability in gabbro below 750 mbsf to 5e-17 m2. The thermal gradient in the upper part of the borehole can be matched with a permeability of 3e-14 m2 in a 750 m thick layer parallel to the surface of the massif, with upflow occurring in areas of high topography and downflow at the location of the borehole. However in 3-D the precise flow pattern is quite model dependent, and the thermal structure can be matched either by downflow centred on the borehole at lower permeability or centred a few hundred metres from the borehole at higher permeability. The borehole gradient is compatible with the longevity (>120 kyr) and outflow temperature (40-90 °C) of the LCHF either with a deep more permeable (1e-14 m2 to 1e-15 m2) domain beneath the vent site in 2-D or a permeable fault slot 500 to 1000m wide and parallel to the transform fault in 3-D. In both cases topography

  8. Evaluation of the Effectiveness of 3D Vascular Stereoscopic Models in Anatomy Instruction for First Year Medical Students

    Cui, Dongmei; Wilson, Timothy D.; Rockhold, Robin W.; Lehman, Michael N.; Lynch, James C.

    2017-01-01

    The head and neck region is one of the most complex areas featured in the medical gross anatomy curriculum. The effectiveness of using three-dimensional (3D) models to teach anatomy is a topic of much discussion in medical education research. However, the use of 3D stereoscopic models of the head and neck circulation in anatomy education has not…

  9. An intelligent recovery progress evaluation system for ACL reconstructed subjects using integrated 3-D kinematics and EMG features.

    Malik, Owais A; Senanayake, S M N Arosha; Zaheer, Dansih

    2015-03-01

    An intelligent recovery evaluation system is presented for objective assessment and performance monitoring of anterior cruciate ligament reconstructed (ACL-R) subjects. The system acquires 3-D kinematics of tibiofemoral joint and electromyography (EMG) data from surrounding muscles during various ambulatory and balance testing activities through wireless body-mounted inertial and EMG sensors, respectively. An integrated feature set is generated based on different features extracted from data collected for each activity. The fuzzy clustering and adaptive neuro-fuzzy inference techniques are applied to these integrated feature sets in order to provide different recovery progress assessment indicators (e.g., current stage of recovery, percentage of recovery progress as compared to healthy group, etc.) for ACL-R subjects. The system was trained and tested on data collected from a group of healthy and ACL-R subjects. For recovery stage identification, the average testing accuracy of the system was found above 95% (95-99%) for ambulatory activities and above 80% (80-84%) for balance testing activities. The overall recovery evaluation performed by the proposed system was found consistent with the assessment made by the physiotherapists using standard subjective/objective scores. The validated system can potentially be used as a decision supporting tool by physiatrists, physiotherapists, and clinicians for quantitative rehabilitation analysis of ACL-R subjects in conjunction with the existing recovery monitoring systems.

  10. Clinical evaluation of 2D versus 3D whole-body PET image quality using a dedicated BGO PET scanner

    Visvikis, D. [CHU Morvan, U650 INSERM, Laboratoire de Traitement de l' Information Medicale (LaTIM), Brest (France); Griffiths, D. [Lister Healthcare, London PET Centre, London (United Kingdom); Costa, D.C. [Middlesex Hospital, Institute of Nuclear Medicine, Royal Free and University College Medical School, London (United Kingdom); HPP Medicina Molecular, SA Porto (Portugal); Bomanji, J.; Ell, P.J. [Middlesex Hospital, Institute of Nuclear Medicine, Royal Free and University College Medical School, London (United Kingdom)

    2005-09-01

    Three-dimensional positron emission tomography (3D PET) results in higher system sensitivity, with an associated increase in the detection of scatter and random coincidences. The objective of this work was to compare, from a clinical perspective, 3D and two-dimensional (2D) acquisitions in terms of whole-body (WB) PET image quality with a dedicated BGO PET system. 2D and 3D WB emission acquisitions were carried out in 70 patients. Variable acquisition parameters in terms of time of emission acquisition per axial field of view (aFOV) and slice overlap between sequential aFOVs were used during the 3D acquisitions. 3D and 2D images were reconstructed using FORE+WLS and OSEM respectively. Scatter correction was performed by convolution subtraction and a model-based scatter correction in 2D and 3D respectively. All WB images were attenuation corrected using segmented transmission scans. Images were blindly assessed by three observers for the presence of artefacts, confidence in lesion detection and overall image quality using a scoring system. Statistically significant differences between 2D and 3D image quality were only obtained for 3D emission acquisitions of 3 min. No statistically significant differences were observed for image artefacts or lesion detectability scores. Image quality correlated significantly with patient weight for both modes of operation. Finally, no differences were seen in image artefact scores for the different axial slice overlaps considered, suggesting the use of five slice overlaps in 3D WB acquisitions. 3D WB imaging using a dedicated BGO-based PET scanner offers similar image quality to that obtained in 2D considering similar overall times of acquisitions. (orig.)

  11. 3D photoacoustic imaging

    Carson, Jeffrey J. L.; Roumeliotis, Michael; Chaudhary, Govind; Stodilka, Robert Z.; Anastasio, Mark A.

    2010-06-01

    Our group has concentrated on development of a 3D photoacoustic imaging system for biomedical imaging research. The technology employs a sparse parallel detection scheme and specialized reconstruction software to obtain 3D optical images using a single laser pulse. With the technology we have been able to capture 3D movies of translating point targets and rotating line targets. The current limitation of our 3D photoacoustic imaging approach is its inability ability to reconstruct complex objects in the field of view. This is primarily due to the relatively small number of projections used to reconstruct objects. However, in many photoacoustic imaging situations, only a few objects may be present in the field of view and these objects may have very high contrast compared to background. That is, the objects have sparse properties. Therefore, our work had two objectives: (i) to utilize mathematical tools to evaluate 3D photoacoustic imaging performance, and (ii) to test image reconstruction algorithms that prefer sparseness in the reconstructed images. Our approach was to utilize singular value decomposition techniques to study the imaging operator of the system and evaluate the complexity of objects that could potentially be reconstructed. We also compared the performance of two image reconstruction algorithms (algebraic reconstruction and l1-norm techniques) at reconstructing objects of increasing sparseness. We observed that for a 15-element detection scheme, the number of measureable singular vectors representative of the imaging operator was consistent with the demonstrated ability to reconstruct point and line targets in the field of view. We also observed that the l1-norm reconstruction technique, which is known to prefer sparseness in reconstructed images, was superior to the algebraic reconstruction technique. Based on these findings, we concluded (i) that singular value decomposition of the imaging operator provides valuable insight into the capabilities of

  12. 3D-Ultrasonography for evaluation of facial muscles in patients with chronic facial palsy or defective healing: a pilot study

    Volk, Gerd Fabian; Pohlmann, Martin; Finkensieper, Mira; Chalmers, Heather J.; Guntinas-Lichius, Orlando

    2014-01-01

    Background While standardized methods are established to examine the pathway from motorcortex to the peripheral nerve in patients with facial palsy, a reliable method to evaluate the facial muscles in patients with long-term palsy for therapy planning is lacking. Methods A 3D ultrasonographic (US) acquisition system driven by a motorized linear mover combined with conventional US probe was used to acquire 3D data sets of several facial muscles on both sides of the face in a healthy subject an...

  13. Evaluation of spatial and temporal root water uptake patterns of a flood-irrigated pecan tree using the hydrus (2D/3D) model

    Deb, SK; Shukla, MK; J. Šimůnek; Mexal, JG

    2013-01-01

    Quantitative information about the spatial and temporal patterns of compensatory root water uptake (RWU) in flood-irrigated pecan orchard is limited. We evaluated spatio-temporal compensated and uncompensated RWU patterns of mature pecan tree in a silty clay loam orchard using the HYDRUS (2D/3D) model. HYDRUS (2D/3D) simulations, which agreed well with measured water contents and temperatures at different soil depths and horizontal distances from the tree trunk, suggested that while both comp...

  14. Measurements and ALE3D Simulations for Violence in a Scaled Thermal Explosion Experiment with LX-10 and AerMet 100 Steel

    McClelland, M A; Maienschein, J L; Yoh, J J; deHaven, M R; Strand, O T

    2005-06-03

    We completed a Scaled Thermal Explosion Experiment (STEX) and performed ALE3D simulations for the HMX-based explosive, LX-10, confined in an AerMet 100 (iron-cobalt-nickel alloy) vessel. The explosive was heated at 1 C/h until cookoff at 182 C using a controlled temperature profile. During the explosion, the expansion of the tube and fragment velocities were measured with strain gauges, Photonic-Doppler-Velocimeters (PDVs), and micropower radar units. These results were combined to produce a single curve describing 15 cm of tube wall motion. A majority of the metal fragments were captured and cataloged. A fragment size distribution was constructed, and a typical fragment had a length scale of 2 cm. Based on these results, the explosion was considered to be a violent deflagration. ALE3D models for chemical, thermal, and mechanical behavior were developed for the heating and explosive processes. A four-step chemical kinetics model is employed for the HMX while a one-step model is used for the Viton. A pressure-dependent deflagration model is employed during the expansion. The mechanical behavior of the solid constituents is represented by a Steinberg-Guinan model while polynomial and gamma-law expressions are used for the equation of state of the solid and gas species, respectively. A gamma-law model is employed for the air in gaps, and a mixed material model is used for the interface between air and explosive. A Johnson-Cook model with an empirical rule for failure strain is used to describe fracture behavior. Parameters for the kinetics model were specified using measurements of the One-Dimensional-Time-to-Explosion (ODTX), while measurements for burn rate were employed to determine parameters in the burn front model. The ALE3D models provide good predictions for the thermal behavior and time to explosion, but the predicted wall expansion curve is higher than the measured curve. Possible contributions to this discrepancy include inaccuracies in the chemical models

  15. 3D computed tomographic evaluation of the upper airway space of patients undergoing mandibular distraction osteogenesis for micrognathia.

    Bianchi, A; Betti, E; Badiali, G; Ricotta, F; Marchetti, C; Tarsitano, A

    2015-10-01

    Mandibular distraction osteogenesis (MDO) is currently an accepted method of treatment for patients requiring reconstruction of hypoplastic mandibles. To date one of the unsolved problems is how to assess the quantitative increase of mandible length needed to achieve a significant change in the volume of the posterior airway space (PAS) in children with mandibular micrognathia following distraction osteogenesis. The purpose of this study is to present quantitative volumetric evaluation of PAS in young patients having distraction osteogenesis for micrognathia using 3D-CT data sets and compare it with pre-operative situation. In this observational retrospective study, we report our experience in five consecutive patients who underwent MDO in an attempt to relieve severe upper airway obstruction. Each patient was evaluated before treatment (T0) and at the end of distraction procedure (T1) with computer tomography (CT) in axial, coronal, and sagittal planes and three-dimensional CT of the facial bones and upper airway. Using parameters to extract only data within anatomic constraints, a digital set of the edited upper airway volume was obtained. The volume determination was used for volumetric qualification of upper airway. The computed tomographic digital data were used to evaluate the upper airway volumes both pre-distraction and post-distraction. The mean length of distraction was 23 mm. Quantitative assessment of upper airway volume before and after distraction demonstrated increased volumes ranging from 84% to 3,087% with a mean of 536%. In conclusion, our study seems to show that DO can significantly increase the volume of the PAS in patients with upper airway obstruction following micrognathia, by an average of 5 times. Furthermore, the worse is the starting volume, the greater the increase in PAS to equal distraction.

  16. Genotoxicity of quinolones: substituents contribution and transformation products QSAR evaluation using 2D and 3D models.

    Li, Min; Wei, Dongbin; Zhao, Huimin; Du, Yuguo

    2014-01-01

    The genotoxicity of 21 quinolones antibiotics was determined using SOS/umu assay. Some quinolones exhibited high genotoxicity, and the chemical substituent on quinolone ring significantly affected genotoxicity. To establish the relationship between genotoxicity and substituent, a 2D-QSAR model based on quantum chemical parameters was developed. Calculation suggested that both steric and electrostatic properties were correlated well with genotoxicity. Furthermore, the specific effect on three key active sites (1-, 7- and 8-positions) of quinolone ring was investigated using a 3D-QSAR (comparative molecular field analysis, CoMFA) method. From our modeling, the genotoxicity increased when substituents had: (1) big volume and/or positive charge at 1-position; (2) negative charge at 7-position; and (3) small volume and/or negative charge at 8-position. The developed QSAR models were applicable to estimate genotoxicity of quinolones antibiotics and their transformation products. It is noted that some of the transformation products exhibited higher genotoxicity comparing to their precursor (e.g., ciprofloxacin). This study provided an alternative way to understand the molecule genotoxicity of quinolones derivatives, as well as to evaluate their potential environmental risks.

  17. CAD/CAM-designed 3D-printed electroanalytical cell for the evaluation of nanostructured gas-diffusion electrodes

    Chervin, Christopher N.; Parker, Joseph F.; Nelson, Eric S.; Rolison, Debra R.; Long, Jeffrey W.

    2016-04-01

    The ability to effectively screen and validate gas-diffusion electrodes is critical to the development of next-generation metal-air batteries and regenerative fuel cells. The limiting electrode in a classic two-terminal device such as a battery or fuel cell is difficult to discern without an internal reference electrode, but the flooded electrolyte characteristic of three-electrode electroanalytical cells negates the prime function of an air electrode—a void volume freely accessible to gases. The nanostructured catalysts that drive the energy-conversion reactions (e.g., oxygen reduction and evolution in the air electrode of metal-air batteries) are best evaluated in the electrode structure as-used in the practical device. We have designed, 3D-printed, and characterized an air-breathing, thermodynamically referenced electroanalytical cell that allows us to mimic the Janus arrangement of the gas-diffusion electrode in a metal-air cell: one face freely exposed to gases, the other wetted by electrolyte.

  18. A 3D reconstruction method of the body envelope from biplanar X-rays: Evaluation of its accuracy and reliability.

    Nérot, Agathe; Choisne, Julie; Amabile, Célia; Travert, Christophe; Pillet, Hélène; Wang, Xuguang; Skalli, Wafa

    2015-12-16

    The aim of this study was to propose a novel method for reconstructing the external body envelope from the low dose biplanar X-rays of a person. The 3D body envelope was obtained by deforming a template to match the surface profiles in two X-rays images in three successive steps: global morphing to adopt the position of a person and scale the template׳s body segments, followed by a gross deformation and a fine deformation using two sets of pre-defined control points. To evaluate the method, a biplanar X-ray acquisition was obtained from head to foot for 12 volunteers in a standing posture. Up to 172 radio-opaque skin markers were attached to the body surface and used as reference positions. Each envelope was reconstructed three times by three operators. Results showed a bias lower than 7mm and a confidence interval (95%) of reproducibility lower than 6mm for all body parts, comparable to other existing methods matching a template onto stereographic photographs. The proposed method offers the possibility of reconstructing body shape in addition to the skeleton using a low dose biplanar X-rays system.

  19. Real-time Generation of Multi-view Naked-eye 3D Vision and Its Evaluation

    追永, 侑平; OINAGA, Yuhei

    2013-01-01

    In recent years, with the development of three-dimensional imaging technique, as seen in moviesand games such as 3D, stereoscopic video content is becoming more familiar. Among them, theauto-stereoscopic technology can enjoy stereoscopic images without the use of special equipment,e.g., the 3D glasses. Auto-stereoscopic multi-view techniques have been studied by combiningimages which have the minute plurality of viewpoints into one image in focus. However,conventional techniques for generatin...

  20. EVALUATING THE POTENTIAL OF RTK-UAV FOR AUTOMATIC POINT CLOUD GENERATION IN 3D RAPID MAPPING

    H Fazeli; F. Samadzadegan; F. Dadrasjavan

    2016-01-01

    During disaster and emergency situations, 3D geospatial data can provide essential information for decision support systems. The utilization of geospatial data using digital surface models as a basic reference is mandatory to provide accurate quick emergency response in so called rapid mapping activities. The recipe between accuracy requirements and time restriction is considered critical in this situations. UAVs as alternative platforms for 3D point cloud acquisition offer potential...

  1. Evaluation of interface models for 3D-1D coupling of compressible Euler methods for the application on cavitating flows

    Deininger Martina

    2013-01-01

    Full Text Available Numerical simulations of complete hydraulic systems (e.g. diesel injectors can, due to high computational costs, currently not be done entirely in three dimensions. Our aim is to substitute the 3D solver by a corresponding 1D method in some parts of the system and develop a solver coupling with suitable interface models. Firstly, we investigate an interface model for non-cavitating flow passing the interface. A flux-coupling with a thin interface approach is considered and the jump in dimensions at the interface is transferred to an additional variable φ, which switches between the 3D and the 1D domain. As shown in two testcases, the error introduced in the vicinity of the interface is quite small. Two numerical flux formulations for the flux over the 3D-1D interface are compared and the Roe-type flux formulation is recommended. Secondly, extending the first method to cavitating flows passing the interface, we divide the density equation in two equations - one for liquid and one for vapor phase of the two-phase fluid - and couple the two equations by source terms depending on the free enthalpy. We propose two interface models for coupling 3D and 1D compressible density-based Euler methods that have potential for considering the entire (non- cavitating hydraulic system behaviour by a 1D method in combination with an embedded detailed 3D simulation at much lower computational costs than the pure 3D simulation.

  2. The influence of the IMRT QA set-up error on the 2D and 3D gamma evaluation method as obtained by using Monte Carlo simulations

    Kim, Kyeong-Hyeon; Kim, Dong-Su; Kim, Tae-Ho; Kang, Seong-Hee; Cho, Min-Seok; Suh, Tae Suk

    2015-11-01

    The phantom-alignment error is one of the factors affecting delivery quality assurance (QA) accuracy in intensity-modulated radiation therapy (IMRT). Accordingly, a possibility of inadequate use of spatial information in gamma evaluation may exist for patient-specific IMRT QA. The influence of the phantom-alignment error on gamma evaluation can be demonstrated experimentally by using the gamma passing rate and the gamma value. However, such experimental methods have a limitation regarding the intrinsic verification of the influence of the phantom set-up error because experimentally measuring the phantom-alignment error accurately is impossible. To overcome this limitation, we aimed to verify the effect of the phantom set-up error within the gamma evaluation formula by using a Monte Carlo simulation. Artificial phantom set-up errors were simulated, and the concept of the true point (TP) was used to represent the actual coordinates of the measurement point for the mathematical modeling of these effects on the gamma. Using dose distributions acquired from the Monte Carlo simulation, performed gamma evaluations in 2D and 3D. The results of the gamma evaluations and the dose difference at the TP were classified to verify the degrees of dose reflection at the TP. The 2D and the 3D gamma errors were defined by comparing gamma values between the case of the imposed phantom set-up error and the TP in order to investigate the effect of the set-up error on the gamma value. According to the results for gamma errors, the 3D gamma evaluation reflected the dose at the TP better than the 2D one. Moreover, the gamma passing rates were higher for 3D than for 2D, as is widely known. Thus, the 3D gamma evaluation can increase the precision of patient-specific IMRT QA by applying stringent acceptance criteria and setting a reasonable action level for the 3D gamma passing rate.

  3. 3D Animation Essentials

    Beane, Andy

    2012-01-01

    The essential fundamentals of 3D animation for aspiring 3D artists 3D is everywhere--video games, movie and television special effects, mobile devices, etc. Many aspiring artists and animators have grown up with 3D and computers, and naturally gravitate to this field as their area of interest. Bringing a blend of studio and classroom experience to offer you thorough coverage of the 3D animation industry, this must-have book shows you what it takes to create compelling and realistic 3D imagery. Serves as the first step to understanding the language of 3D and computer graphics (CG)Covers 3D anim

  4. 3D video

    Lucas, Laurent; Loscos, Céline

    2013-01-01

    While 3D vision has existed for many years, the use of 3D cameras and video-based modeling by the film industry has induced an explosion of interest for 3D acquisition technology, 3D content and 3D displays. As such, 3D video has become one of the new technology trends of this century.The chapters in this book cover a large spectrum of areas connected to 3D video, which are presented both theoretically and technologically, while taking into account both physiological and perceptual aspects. Stepping away from traditional 3D vision, the authors, all currently involved in these areas, provide th

  5. Thermal effusivity measurement based on analysis of 3D heat flow by modulated spot heating using a phase lag matrix with a combination of thermal effusivity and volumetric heat capacity

    Ohta, Hiromichi; Hatori, Kimihito; Matsui, Genzou; Yagi, Takashi; Miyake, Shugo; Okamura, Takeo; Endoh, Ryo; Okada, Ryo; Morishita, Keisuke; Yokoyama, Shinichiro; Taguchi, Kohei; Kato, Hideyuki

    2016-11-01

    The study goal was to establish a standard industrial procedure for the measurement of thermal effusivity by a thermal microscope (TM), using a periodic heating method with a thermoreflectance (TR) technique. To accomplish this goal, a working group was organized that included four research institutes. Each institute followed the same procedure: a molybdenum (Mo) film was sputtered on the surface of Pyrex, yttria-stabilized zirconia (YSZ), alumina (Al2O3), Germanium (Ge), and silicon (Si) samples, and then the phase lag of the laser intensity modulation was measured by the resultant surface temperature. A procedure was proposed to calibrate the effect of 3D heat flow, based on the analytical solution of the heat conduction equation, and thermal effusivity was measured. The derived values show good agreement with literature values. As a result, the TM calibration procedure can be recommended for practical use in measuring the thermal effusivity in a small region of the materials.

  6. Evaluation of the relationship between renal function and renal volume-vascular indices using 3D power Doppler ultrasound

    Cansu, Aysegul, E-mail: drcansu@gmail.com; Kupeli, Ali; Kul, Sibel; Eyuboglu, Ilker; Oguz, Sukru; Ozturk, Mehmet Halil; Dinc, Hasan

    2014-07-15

    Purpose: To investigate the relationship between renal function and total renal volume-vascular indices using 3D power Doppler ultrasound (3DPDUS). Materials and methods: One hundred six patients with hypertensive proteinuric nephropathy (HPN) (49 male, 57 female) and 65 healthy controls (32 male, 33 female) were evaluated prospectively using 3DPDUS. Total renal volume (RV), vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were calculated using Virtual Organ Computer-aided Analysis (VOCAL). The estimated glomerular filtration rates (GFRs) of the patients with HPN and the control group were calculated. The patients with HPN were divided into two groups on the basis of GFR, normal (≥90) or reduced (<90). Differences between groups were compared using ANOVA. Correlations between GFR, renal volume and vascular indices were analyzed using Pearson's correlation analysis. Significance was set at p < 0.05. Results: The mean total RV, VI, FI and VFI values in the reduced GFR, normal GFR and control groups were RV (ml): 234.7, 280.7 and 294.6; VI: 17.6, 27.6 and 46.8; FI: 79.1, 88.7 and 93.9 and VFI: 7.1, 12.7 and 23.8. There were statistically significant differences between the groups (p < 0.001). Total RVs and vascular indices exhibited significant correlations with estimated GFR (r = 0.53–0.59, p < 0.001) Conclusion: Three-dimensional power Doppler ultrasound is a reliable predictive technique in renal function analysis.

  7. Evaluation of AN Integrated Gis-Based Crime Analysis & 3d Modelling for Izmir-Konak Municipality

    Tarhan, C.; Deniz, D.

    2011-08-01

    GIS integrated 3D modelling is crucial for the city planning and design processes because urban modelling is a tool used in virtual environments, and provides convenience to work. Although, the creation and display of 3D city models for large regions is difficult it is vital for planning and designing safer cities, as well as public places. Today, crime is a significant problem in Turkey. When it was compared by years of crime rates, population growth and urbanization rate, an increasing more than in parallel has been observed. This paper aims to discuss GIS integrated 3D modelling affects in urban planning and design, explaining Turkish planning processes with GIS and 3D modelling. To do that, it presents a case study for Izmir Konak Municipality about GIS integrated crime analysis and 3D models of the crime scenes. Izmir crime records has been obtained from Izmir Police Department belonging to 2003-2004 and 2005 (D. Deniz, 2007) are used for districts' crime map. In the light of these data, the highest rate crime district, Konak, is analyzed between 2001 and 2005 data.

  8. 3D characterization of thermal fatigue damage in monofilament reinforced copper for heat sink applications in fusion reactor systems; 3D-Charakterisierung von thermischer Ermuedungsschaedigung in Monofilament verstaerktem Kupfer zur Anwendung als Waermeleiter in Kernfusionsreaktorsystemen

    Schoebel, Michael; Degischer, H. Peter [Vienna Univ. of Technology (Austria). Inst. of Materials Science and Technology; Brendel, Annegret [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Harrer, Bernhard [Upper Austria Univ. of Applied Sciences, Wels (Austria); Di Michiel, Marco [European Synchrotron Radiation Facility (ESRF), 38 - Grenoble (France)

    2012-07-01

    Monofilament reinforced metals (MFRM) are developed as high temperature heat sink materials for fusion reactor applications. These composites combine the high thermal conductivity (TC) of a Cu matrix with low thermal expansion (CTE) of SiC or W filaments. The CTE mismatch between matrix and reinforcement lead to high micro stresses under operation conditions. Stress induced thermal fatigue damage such as interface delamination and fiber/matrix damage degrades the thermal properties of these composites. Different interface designs are developed for SiC as well as W filaments to improve bonding strength and increase the long term stability. Conventional as well as synchrotron tomography was applied on different MFRMs to characterize thermal fatigue damage and its propagation before, during and after thermal cycling. (orig.)

  9. 3D joint inversion using seismic data and marine controlled-source electromagnetic data for evaluating gas hydrate concentrations

    Kim, B.; Byun, J.; Seol, S. J.; Jeong, S.; Chung, Y.; Kwon, T.

    2015-12-01

    For many decades, gas hydrates have been received great attention as a potential source of natural gas. Therefore, the detailed information of structures of buried gas hydrates and their concentrations are prerequisite for the production for the gas hydrate as a reliable source of alternate energy. Recently, for this reason, a lot of gas hydrate assessment methods have been proposed by many researchers. However, it is still necessary to establish as new method for the further improvement of the accuracy of the 3D gas hydrate distribution. In this study, we present a 3D joint inversion method that provides superior quantitative information of gas hydrate distributions using 3D seismic data obtained by ocean-bottom cable (OBC) and marine controlled-source electromagnetic (CSEM) data. To verify our inversion method, we first built the general 3D gas hydrate model containing vertical methane-flow pathways. With the described model, we generated synthetic 3D OBC data and marine CSEM data using finite element modeling algorithms, respectively. In the joint inversion process, to obtain the high-resolution volumetric P-wave velocity structure, we applied the 3D full waveform inversion algorithm to the acquired OBC data. After that, the obtained P-wave velocity model is used as the structure constraint to compute cross-gradients with the updated resistivity model in the EM inversion process. Finally, petrophysical relations were applied to estimate volumetric gas hydrate concentrations. The proposed joint inversion process makes possible to obtain more precise quantitative gas hydrate assessment than inversion processes using only seismic or EM data. This technique can be helpful for accurate decision-making in gas hydrate development as well as in their production monitoring.

  10. Formulation of Aminosilica Adsorbents into 3D-Printed Monoliths and Evaluation of Their CO2 Capture Performance.

    Thakkar, Harshul; Eastman, Stephen; Al-Mamoori, Ahmed; Hajari, Amit; Rownaghi, Ali A; Rezaei, Fateme

    2017-03-01

    Amine-based materials have represented themselves as a promising class of CO2 adsorbents; however, their large-scale implementation requires their formulation into suitable structures. In this study, we report formulation of aminosilica adsorbents into monolithic structures through a three-dimensional (3D) printing technique. In particular, 3D-printed monoliths were fabricated using presynthesized silica-supported tetraethylenepentamine (TEPA) and poly(ethylenimine) (PEI) adsorbents using three different approaches. In addition, a 3D-printed bare silica monolith was prepared and post-functionalized with 3-aminopropyltrimethoxysilane (APS). Characterization of the obtained monoliths indicated that aminosilica materials retained their characteristics after being extruded into 3D-printed configurations. Adsorptive performance of amine-based structured adsorbents was also investigated in CO2 capture. Our results indicated that aminosilica materials retain their structural, physical, and chemical properties in the monoliths. In addition, the aminosilica monoliths exhibited adsorptive characteristics comparable to their corresponding powders. This work highlights the importance of adsorbent materials formulations into practical contactors such as monoliths, as the scalabale technology platform, that could facilitate rapid deployment of adsorption-based CO2 capture processes on commercial scales.

  11. Dimensional evaluation of patient-specific 3D printing using calcium phosphate cement for craniofacial bone reconstruction.

    Bertol, Liciane Sabadin; Schabbach, Rodrigo; Dos Santos, Luís Alberto Loureiro

    2016-12-01

    The 3D printing process is highlighted nowadays as a possibility to generate individual parts with complex geometries. Moreover, the development of 3D printing hardware, software and parameters permits the manufacture of parts that can be not only used as prototypes, but are also made from materials that are suitable for implantation. In this way, this study investigates the process involved in the production of patient-specific craniofacial implants using calcium phosphate cement, and its dimensional accuracy. The implants were previously generated in a computer-aided design environment based on the patient's tomographic data. The fabrication of the implants was carried out in a commercial 3D powder printing system using alfa-tricalcium phosphate powder and an aqueous solution of Na2HPO4 as a binder. The fit of the 3D printed implants was measured by three-dimensional laser scanning and by checking the right adjustment to the patient's anatomical biomodel. The printed parts presented a good degree of fitting and accuracy.

  12. 3D Skeleton model derived from Kinect Depth Sensor Camera and its application to walking style quality evaluations

    Kohei Arai

    2013-07-01

    Full Text Available Feature extraction for gait recognition has been created widely. The ancestor for this task is divided into two parts, model based and free-model based. Model-based approaches obtain a set of static or dynamic skeleton parameters via modeling or tracking body components such as limbs, legs, arms and thighs. Model-free approaches focus on shapes of silhouettes or the entire movement of physical bodies. Model-free approaches are insensitive to the quality of silhouettes. Its advantage is a low computational costs comparing to model-based approaches. However, they are usually not robust to viewpoints and scale. Imaging technology also developed quickly this decades. Motion capture (mocap device integrated with motion sensor has an expensive price and can only be owned by big animation studio. Fortunately now already existed Kinect camera equipped with depth sensor image in the market with very low price compare to any mocap device. Of course the accuracy not as good as the expensive one, but using some preprocessing we can remove the jittery and noisy in the 3D skeleton points. Our proposed method is part of model based feature extraction and we call it 3D Skeleton model. 3D skeleton model for extracting gait itself is a new model style considering all the previous model is using 2D skeleton model. The advantages itself is getting accurate coordinate of 3D point for each skeleton model rather than only 2D point. We use Kinect to get the depth data. We use Ipisoft mocap software to extract 3d skeleton model from Kinect video. From the experimental results shows 86.36% correctly classified instances using SVM.

  13. Evaluation of a 3-D interactive tooth atlas by dental students in dental anatomy and endodontics courses.

    Wright, Edward F; Hendricson, William D

    2010-02-01

    Advances in information and communication technology continually offer innovations to assist faculty in their efforts to help students learn new information or develop new skills. However, faculty members are often hesitant to incorporate these innovations into their courses out of fear that these new methods may not provide the anticipated outcomes. Hence, students are often the subjects of educational trials to evaluate curriculum innovations by comparing a new teaching/learning method to traditional lecture-based instruction. The most typical finding is that students can learn equally well by either method. However, two questions that have not been studied extensively in dental education are whether dental students will actually use computer-based educational resources made available to them and whether students perceive these materials to provide a value-added learning experience. Accordingly, the goals of this study were to determine whether first-year dental students (D1), second-year dental students (D2), and third-year dental students (D3) would 1) use an interactive tooth atlas, available on a DVD, as a study aid and 2) perceive that the atlas provided sufficient value-added benefit for their dental anatomy (D1), preclinical laboratory endodontics (D2), and clinical endodontics (D3) courses to recommend adding it to their school's comprehensive electronic resources. A low percentage of the students (14 percent; 40/289) voluntarily downloaded the atlas from a DVD to their laptops prior to the addition of incentives in the form of atlas-related examination questions. Even after incentives were added, only 43 percent of the students (126/289) downloaded the DVD. After using the atlas, students responded to the statement "Using the 3D Interactive Tooth Atlas was beneficial for me" on a 0 to 10 scale with 0 representing strongly disagree, 5 representing unsure, and 10 representing strongly agree. The mean rankings were 5.34 for D1s, 6.79 for D2s, and 7.28 for D

  14. 3D evaluation of the lamina cribrosa with swept-source optical coherence tomography in normal tension glaucoma.

    Kazuko Omodaka

    Full Text Available Although the lamina cribrosa (LC is the primary site of axonal damage in glaucoma, adequate methods to image and measure it are currently lacking. Here, we describe a noninvasive, in vivo method of evaluating the LC, based on swept-source optical coherence tomography (SS-OCT, and determine this method's ability to quantify LC thickness.This study comprised 54 eyes, including normal (n = 18, preperimetric glaucoma (PPG; n = 18, and normal tension glaucoma (NTG; n = 18 eyes. We used SS-OCT to obtain 3 x 3 mm cube scans of an area centered on the optic disc, and then synchronized reconstructed B- and en-face images from this data. We identified the LC in these B-scan images by marking the visible borders of the LC pores. We marked points on the anterior and posterior borders of the LC in 12 B-scan images in order to create a skeleton model of the LC. Finally, we used B-spline interpolation to form a 3D model of the LC, including only reliably measured scan areas. We calculated the average LC thickness (avgLCT in this model and used Spearman's rank correlation coefficient to compare it with circumpapillary retinal nerve fiber layer thickness (cpRNFLT.We found that the correlation coefficient of avgLCT and cpRNFLT was 0.64 (p < 0.01. The coefficient of variation for avgLCT was 5.1%. AvgLCT differed significantly in the groups (normal: 282.6 ± 20.6 μm, PPG: 261.4 ± 15.8 μm, NTG: 232.6 ± 33.3 μm. The normal, PPG and NTG groups did not significantly differ in age, sex, refractive error or intraocular pressure (IOP, although the normal and NTG groups differed significantly in cpRNFLT and Humphrey field analyzer measurements of mean deviation.Thus, our results indicate that the parameters of our newly developed method of measuring LC thickness with SS-OCT may provide useful and important data for glaucoma diagnosis and research.

  15. Evaluation of the cytotoxic effects of ophthalmic solutions containing benzalkonium chloride on corneal epithelium using an organotypic 3-D model

    Khoh-Reiter, Su; Jessen, Bart A

    2009-01-01

    Background Benzalkonium chloride (BAC) is a common preservative used in ophthalmic solutions. The aim of this study was to compare the cytotoxic effects of BAC-containing ophthalmic solutions with a BAC-free ophthalmic solution using an organotypic 3-dimensional (3-D) corneal epithelial model and to determine the effects of latanoprost ophthalmic solution and its BAC-containing vehicle on corneal thickness in a monkey model. Methods The cytotoxicity of commercially available BAC-containing ophthalmic formulations of latanoprost (0.02% BAC) and olopatadine (0.01% BAC) was compared to that of BAC-free travoprost and saline in a corneal organotypic 3-D model using incubation times of 10 and 25 minutes. To compare the extent of differentiation of 3-D corneal cultures to monolayer transformed human corneal epithelial (HCE-T) cell cultures, expression levels (mRNA and protein) of the corneal markers epidermal growth factor receptor, transglutaminase 1 and involucrin were quantified. Finally, latanoprost ophthalmic solution or its vehicle was administered at suprapharmacologic doses (two 30 μL drops twice daily in 1 eye for 1 year) in monkey eyes, and corneal pachymetry was performed at baseline and at weeks 4, 13, 26 and 52. Results In the 3-D corneal epithelial culture assays, there were no significant differences in cytotoxicity between the BAC-containing latanoprost and olopatadine ophthalmic solutions and BAC-free travoprost ophthalmic solution at either the 10- or 25-minute time points. The 3-D cultures expressed higher levels of corneal epithelial markers than the HCE-T monolayers, indicating a greater degree of differentiation. There were no significant differences between the corneal thickness of monkey eyes treated with latanoprost ophthalmic solution or its vehicle (both containing 0.02% BAC) and untreated eyes. Conclusion The lack of cytotoxicity demonstrated in 3-D corneal cultures and in monkey studies suggests that the levels of BAC contained in ophthalmic

  16. Evaluation of the cytotoxic effects of ophthalmic solutions containing benzalkonium chloride on corneal epithelium using an organotypic 3-D model

    Jessen Bart A

    2009-07-01

    Full Text Available Abstract Background Benzalkonium chloride (BAC is a common preservative used in ophthalmic solutions. The aim of this study was to compare the cytotoxic effects of BAC-containing ophthalmic solutions with a BAC-free ophthalmic solution using an organotypic 3-dimensional (3-D corneal epithelial model and to determine the effects of latanoprost ophthalmic solution and its BAC-containing vehicle on corneal thickness in a monkey model. Methods The cytotoxicity of commercially available BAC-containing ophthalmic formulations of latanoprost (0.02% BAC and olopatadine (0.01% BAC was compared to that of BAC-free travoprost and saline in a corneal organotypic 3-D model using incubation times of 10 and 25 minutes. To compare the extent of differentiation of 3-D corneal cultures to monolayer transformed human corneal epithelial (HCE-T cell cultures, expression levels (mRNA and protein of the corneal markers epidermal growth factor receptor, transglutaminase 1 and involucrin were quantified. Finally, latanoprost ophthalmic solution or its vehicle was administered at suprapharmacologic doses (two 30 μL drops twice daily in 1 eye for 1 year in monkey eyes, and corneal pachymetry was performed at baseline and at weeks 4, 13, 26 and 52. Results In the 3-D corneal epithelial culture assays, there were no significant differences in cytotoxicity between the BAC-containing latanoprost and olopatadine ophthalmic solutions and BAC-free travoprost ophthalmic solution at either the 10- or 25-minute time points. The 3-D cultures expressed higher levels of corneal epithelial markers than the HCE-T monolayers, indicating a greater degree of differentiation. There were no significant differences between the corneal thickness of monkey eyes treated with latanoprost ophthalmic solution or its vehicle (both containing 0.02% BAC and untreated eyes. Conclusion The lack of cytotoxicity demonstrated in 3-D corneal cultures and in monkey studies suggests that the levels of BAC

  17. 3-D multi-observable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle. II: General methodology and resolution analysis

    Afonso, J. C.; Fullea, J.; Yang, Y.; Connolly, J. A. D.; Jones, A. G.

    2013-04-01

    Here we present a 3-D multi-observable probabilistic inversion method, particularly designed for high-resolution (regional) thermal and compositional mapping of the lithosphere and sub-lithospheric upper mantle that circumvents the problems associated with traditional inversion methods. The key aspects of the method are as follows: (a) it exploits the increasing amount and quality of geophysical datasets; (b) it combines multiple geophysical observables (Rayleigh and Love dispersion curves, body-wave tomography, magnetotelluric, geothermal, petrological, gravity, elevation, and geoid) with different sensitivities to deep/shallow, thermal/compositional anomalies into a single thermodynamic-geophysical framework; (c) it uses a general probabilistic (Bayesian) formulation to appraise the data; (d) no initial model is needed; (e) compositional a priori information relies on robust statistical analyses of a large database of natural mantle samples; and (f) it provides a natural platform to estimate realistic uncertainties. In addition, the modular nature of the method/algorithm allows for incorporating or isolating specific forward operators according to available data. The strengths and limitations of the method are thoroughly explored with synthetic models. It is shown that the a posteriori probability density function (i.e., solution to the inverse problem) satisfactorily captures spatial variations in bulk composition and temperature with high resolution, as well as sharp discontinuities in these fields. Our results indicate that only temperature anomalies of ΔT ⪆150°C and large compositional anomalies of ΔMg# > 3 (or bulk ΔAl2O3 > 1.5) can be expected to be resolved simultaneously when combining high-quality geophysical data. This resolving power is sufficient to explore some long-standing problems regarding the nature and evolution of the lithosphere (e.g., vertical stratification of cratonic mantle, compositional versus temperature signatures in seismic

  18. The value of 3D T1-weighted gradient-echo MR imaging for evaluation of the appendix during pregnancy: preliminary results

    Jang, Kyung Mi; Kim, Seong Hyun; Choi, Dongil; Lee, Soon Jin; Rhim, Hyunchul; Park, Min Jung (Depts. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)), email: kshyun@skku.edu

    2011-10-15

    Background The use of oral contrast has been essential for the identification of a normal appendix on MR imaging during pregnancy. However, stool could be used as a positive oral contrast as it is characterized by a relatively high signal on T1-weighted imaging, and 3D T1-weighted gradient-echo (T1W-GRE) MR imaging has been used to evaluate 3 mm diameter intestines in fetuses. Purpose To evaluate the added value of 3D T1W-GRE MR imaging in combination with T2-weighted imaging (T2WI) compared to T2WI alone for evaluating the appendix during pregnancy. Material and Methods Eighteen consecutive pregnant patients who were clinically suspected of having acute appendicitis underwent appendix MR imaging which included T2WI with or without spectral presaturation attenuated inversion-recovery (SPAIR) fat suppression, and 3D T1W-GRE with SPAIR fat suppression. Two radiologists reviewed the two image sets (the T2WI set and the combined set of T2WI and 3D T1W-GRE images). Pathologic and clinical results served as the reference standard. The differences in the degree of visibility of the appendix and confidence scale for diagnosing acute appendicitis between two image sets were compared by using the paired Wilcoxon signed rank test. Results For both reviewers, the degree of visibility of the appendix using the combined T2WI and 3D T1W-GRE images was significantly higher than using T2WI alone (P < 0.01), and the confidence levels for acute appendicitis using combined T2WI and 3D T1W-GRE images were significantly different from those using T2WI alone (P < 0.01). In the 13 patients with a normal appendix, both reviewers showed improved confidence levels for appendicitis using combined T2WI and 3D T1W-GRE images than T2WI alone. Conclusion Adding 3D T1W-GRE images to T2WI is helpful for identification of the appendix, as compared to T2WI alone in pregnant women without ingestion of oral contrast material. This may improve diagnostic confidence for acute appendicitis in pregnant

  19. Accuracy evaluation of a 3D-printed individual template for needle guidance in head and neck brachytherapy

    Huang, Ming-Wei; Zhang, Jian-Guo; Zheng, Lei; Liu, Shu-Ming; Yu, Guang-Yan

    2016-01-01

    To transfer the preplan for the head and neck brachytherapy to the clinical implantation procedure, a preplan-based 3D-printed individual template for needle insertion guidance had previously been designed and used. The accuracy of needle insertion using this kind template was assessed in vivo. In the study, 25 patients with head and neck tumors were implanted with 125I radioactive seeds under the guidance of the 3D-printed individual template. Patients were divided into four groups based on the site of needle insertion: the parotid and masseter region group (nine patients); the maxillary and paranasal region group (eight patients); the submandibular and upper neck area group (five patients); and the retromandibular region group (six patients). The distance and angular deviations between the preplanned and placed needles were compared, and the complications and time required for needle insertion were assessed. The mean entrance point distance deviation for all 619 needles was 1.18 ± 0.81 mm, varying from 0.857 ± 0.545 to 1.930 ± 0.843 mm at different sites. The mean angular deviation was 2.08 ± 1.07 degrees, varying from 1.85 ± 0.93 to 2.73 ± 1.18 degrees at different sites. All needles were manually inserted to their preplanned positions in a single attempt, and the mean time to insert one needle was 7.5 s. No anatomical complications related to inaccurately placed implants were observed. Using the 3D-printed individual template for the implantation of 125I radioactive seeds in the head and neck region can accurately transfer a CT-based preplan to the brachytherapy needle insertion procedure. Moreover, the addition of individual template guidance can reduce the time required for implantation and minimize the damage to normal tissues. PMID:27422928

  20. Reliability of a new method for evaluating femoral stem positioning after total hip arthroplasty based on stereoradiographic 3D reconstruction.

    Guenoun, Benjamin; El Hajj, Firass; Biau, David; Anract, Philippe; Courpied, Jean-Pierre

    2015-01-01

    The goal of this study was to validate a new method for determining femoral stem positioning based on 3D models derived from the EOS biplanar system. Independents observers measured stem anteversion and femoral offset using CT scan and EOS system of 28 femoral stems implanted in composite femurs. In parallel, the same parameters were measured on biplanar lower limb radiographs acquired from 30 patients who had undergone total hip arthroplasty. CT scanner and biplanar X-ray measurements on composite femurs were highly correlated: 0.94 for femoral offset (P X-ray system.

  1. Automated simulation and evaluation of autostereoscopic multiview 3D display designs by time-sequential and wavelength-selective filter barrier

    Kuhlmey, Mathias; Jurk, Silvio; Duckstein, Bernd; de la Barré, René

    2015-09-01

    A novel simulation tool has been developed for spatial multiplexed 3D displays. Main purpose of our software is the 3D display design with optical image splitter in particular lenticular grids or wavelength-selective barriers. As a result of interaction of image splitter with ray emitting displays a spatial light-modulator generating the autostereoscopic image representation was modeled. Based on the simulation model the interaction of optoelectronic devices with the defined spatial planes is described. Time-sequential multiplexing enables increasing the resolution of such 3D displays. On that reason the program was extended with an intermediate data cumulating component. The simulation program represents a stepwise quasi-static functionality and control of the arrangement. It calculates and renders the whole display ray emission and luminance distribution on viewing distance. The degree of result complexity will increase by using wavelength-selective barriers. Visible images at the viewer's eye positon were determined by simulation after every switching operation of optical image splitter. The summation and evaluation of the resulting data is processed in correspondence to the equivalent time sequence. Hereby the simulation was expanded by a complex algorithm for automated search and validation of possible solutions in the multi-dimensional parameter space. For the multiview 3D display design a combination of ray-tracing and 3D rendering was used. Therefore the emitted light intensity distribution of each subpixel will be evaluated by researching in terms of color, luminance and visible area by using different content distribution on subpixel plane. The analysis of the accumulated data will deliver different solutions distinguished by standards of evaluation.

  2. A procedure for the evaluation of 2D radiographic texture analysis to assess 3D bone micro-architecture; Evaluation de l'analyse de la texture de radiographies 2D pour evaluer les micro architecture 3D d'os

    Apostol, L.; Peyrin, F.; Yot, S.; Basset, O.; Odet, Ch. [CREATIS - Centre National de la Recherche Scientifique (UMR CNRS 5515), 69 - Villeurbanne (France); Apostal, L.; Boller, E. [European Synchrotron Radiation Facility (ESRF), 38 - Grenoble (France); Tabary, J.; Dinten, J.M. [CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI), 38 (France); Boudousq, V.; Kotzki, P.O. [Faculte de Medecine, Lab. de Biophysique Medicale, 30 - Nimes (France)

    2004-07-01

    Although the diagnosis of osteoporosis is mainly based on Dual X-ray Absorptiometry, it has been shown that trabecular bone micro-architecture is also an important factor in regards of fracture risk, which can be efficiently assessed in vitro using three-dimensional x-ray microtomography ({mu}CT). In vivo, techniques based on high-resolution x-ray radiography associated to texture analysis have been proposed to investigate bone micro-architecture, but their relevance for giving pertinent 3D information is unclear. The purpose of this work was to develop a method for evaluating the relationships between 3D micro-architecture and 2D texture parameters, and optimizing the conditions for radiographic imaging. Bone sample images taken from cortical to cortical were acquired using 3D-synchrotron x-ray {mu}CT at the ESRF. The 3D digital images were further used for two purposes: 1) quantification of three-dimensional bone micro-architecture, 2) simulation of realistic x-ray radiographs under different acquisition conditions. Texture analysis was then applied to these 2D radiographs using a large variety of methods (co-occurrence, spectrum, fractal...). First results of the statistical analysis between 2D and 3D parameters allowed identifying the most relevant 2D texture parameters. (authors)

  3. IZDELAVA TISKALNIKA 3D

    Brdnik, Lovro

    2015-01-01

    Diplomsko delo analizira trenutno stanje 3D tiskalnikov na trgu. Prikazan je razvoj in principi delovanja 3D tiskalnikov. Predstavljeni so tipi 3D tiskalnikov, njihove prednosti in slabosti. Podrobneje je predstavljena zgradba in delovanje koračnih motorjev. Opravljene so meritve koračnih motorjev. Opisana je programska oprema za rokovanje s 3D tiskalniki in komponente, ki jih potrebujemo za izdelavo. Diploma se oklepa vprašanja, ali je izdelava 3D tiskalnika bolj ekonomična kot pa naložba v ...

  4. Physics-based Simulation of Human Posture Using 3D Whole Body Scanning Technology for Astronaut Space Suit Evaluation

    Kim, Kyu-Jung

    2005-01-01

    Over the past few years high precision three-dimensional (3D) full body laser scanners have been developed to be used as a powerful anthropometry tool for quantification of the morphology of the human body. The full body scanner can quickly extract body characteristics in non-contact fashion. It is required for the Anthropometry and Biomechanics Facility (ABF) to have capabilities for kinematics simulation of a digital human at various postures whereas the laser scanner only allows capturing a single static posture at each time. During this summer fellowship period a theoretical study has been conducted to estimate an arbitrary posture with a series of example postures through finite element (FE) approximation and found that four-point isoparametric FE approximation would result in reasonable maximum position errors less than 5%. Subsequent pilot scan experiments demonstrated that a bead marker with a nominal size of 6 mm could be used as a marker for digitizing 3-D coordinates of anatomical landmarks for further kinematic analysis. Two sessions of human subject testing were conducted for reconstruction of an arbitrary postures from a set of example postures for each joint motion for the forearm/hand complex and the whole upper extremity.

  5. Comprehensive evaluation of high-steep slope stability and optimal high-steep slope design by 3D physical modeling

    Lai, Xing-ping; Shan, Peng-fei; Cai, Mei-feng; Ren, Fen-hua; Tan, Wen-hui

    2015-01-01

    High-steep slope stability and its optimal excavation design in Shuichang open pit iron mine were analyzed based on a large 3D physical simulation technique. An optimal excavation scheme with a relatively steeper slope angle was successfully implemented at the northwest wall between Nos. 4 and 5 exploration lines of Shuichang Iron Mine, taking into account the 3D scale effect. The physico-mechanical properties of rock materials were obtained by laboratory tests conducted on sample cores from exploration drilling directly from the iron mine. A porous rock-like composite material was formed for the model, and the mechanical parameters of the material were assessed experimentally; specifically, the effect of water on the sample was quantitatively determined. We adopted an experimental setup using stiff modular applied static loading to carry out a visual excavation of the slope at a random depth. The setup was equipped with acoustic emission (AE) sensors, and the experiments were monitored by crack optical acquirement, ground penetrating radar, and close-field photogrammetry to investigate the mechanisms of rock-mass destabilization in the high-steep slope. For the complex study area, the model results indicated a clear correlation between the model's destabilization resulting from slope excavation and the collected monitoring information. During the model simulation, the overall angle of the slope increased by 1-6 degrees in different sections. Dramatically, the modeled excavation scheme saved over 80 million tons of rock from extraction, generating enormous economic and ecological benefits.

  6. SU-F-BRE-06: Evaluation of Patient CT Dose Reconstruction From 3D Diode Array Measurements Using Anthropomorphic Phantoms

    Huang, M; Benhabib, S; Cardan, R; Brezovich, I; Popple, R [The University of Alabama at Birmingham, Birmingham, AL (United States); Faught, A; Followill, D [The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    Purpose: To compare 3D reconstructed dose of IMRT plans from 3D diode array measurements with measurements in anthropomorphic phantoms. Methods: Six IMRT plans were created for the IROC Houston (RPC) head and neck (H and N) and lung phantoms following IROC Houston planning protocols. The plans included flattened and unflattened beam energies ranging from 6 MV to 15 MV and both static and dynamic MLC tecH and Niques. Each plan was delivered three times to the respective anthropomorphic phantom, each of which contained thermoluminescent dosimeters (TLDs) and radiochromic films (RCFs). The plans were also delivered to a Delta4 diode array (Scandidos, Uppsala, Sweden). Irradiations were done using a TrueBeam STx (Varian Medical Systems, Palo Alto, CA). The dose in the patient was calculated by the Delta4 software, which used the diode measurements to estimate incident energy fluence and a kernel-based pencil beam algorithm to calculate dose. The 3D dose results were compared with the TLD and RCF measurements. Results: In the lung, the average difference between TLDs and Delta4 calculations was 5% (range 2%–7%). For the H and N, the average differences were 2.4% (range 0%–4.5%) and 1.1% (range 0%–2%) for the high- and low-dose targets, respectively, and 12% (range 10%-13%) for the organ-at-risk simulating the spinal cord. For the RCF and criteria of 7%/4mm, 5%/3mm, and 3%/3mm, the average gamma-index pass rates were 95.4%, 85.7%, and 76.1%, respectively for the H and N and 76.2%, 57.8%, and 49.5% for the lung. The pass-rate in the lung decreased with increasing beam energy, as expected for a pencil beam algorithm. Conclusion: The H and N phantom dose reconstruction met the IROC Houston acceptance criteria for clinical trials; however, the lung phantom dose did not, most likely due to the inaccuracy of the pencil beam algorithm in the presence of low-density inhomogeneities. Work supported by PHS grant CA10953 and CA81647 (NCI, DHHS)

  7. Unassisted 3D camera calibration

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  8. Preoperative evaluation of neurovascular relationship by using contrast-enhanced and unenhanced 3D time-of-flight MR angiography in patients with trigeminal neuralgia

    Qin, Zhou; Zhiling, Liu; Chuanfu, Li; Qingshi Zeng (Dept. of Radiology, Qilu Hospital of Shandong Univ., Jinan (China)), email: zengqingshi@yahoo.cn; Chuncheng, Qu (Dept. of Neurosurgery, the Second Hospital of Shandong Univ., Jinan (China)); Shilei, Ni (Dept. of Neurosurgery, Qilu Hospital of Shandong Univ., Jinan (China))

    2011-10-15

    Background Microvascular decompression is an etiological strategy for the therapy of trigeminal neuralgia (TN). Preoperative identification of neurovascular compression, therefore, could have an impact on the determination of appropriate treatment for TN. Purpose To evaluate the value of contrast-enhanced and unenhanced three-dimensional (3D) time-of-flight (TOF) MR angiography in the visualization of neurovascular relationship in patients with TN. Material and Methods Thirty-seven patients with unilateral TN underwent unenhanced and contrast-enhanced 3D TOF MR angiography with a 3.0-T MR system. Images were reviewed by a radiologist blinded to clinical details. Vascular contact with the trigeminal nerve was identified, and the nature of the involved vessels (artery or vein) was determined. All patients underwent microvascular decompression. Results In 37 patients with TN, contrast-enhanced 3D TOF MR angiography identified surgically verified neurovascular contact in 35 of 36 symptomatic nerves, and there was no false-positive. Based on surgical findings, the sensitivity of MR imaging was 97.2% and specificity 100%. The nature of the offending vessel was correctly identified in 94.4% of the patients by using the combination of contrast-enhanced and unenhanced MR angiography. Conclusion Contrast-enhanced 3D TOF MR angiography is useful in the detection of vascular contact with the trigeminal nerve in patients with TN, and this MR imaging in combination with unenhanced MR angiography could help in the identification of the nature of the responsible vessels

  9. A synergistic approach to the design, fabrication and evaluation of 3D printed micro and nano featured scaffolds for vascularized bone tissue repair

    Holmes, Benjamin; Bulusu, Kartik; Plesniak, Michael; Zhang, Lijie Grace

    2016-02-01

    3D bioprinting has begun to show great promise in advancing the development of functional tissue/organ replacements. However, to realize the true potential of 3D bioprinted tissues for clinical use requires the fabrication of an interconnected and effective vascular network. Solving this challenge is critical, as human tissue relies on an adequate network of blood vessels to transport oxygen, nutrients, other chemicals, biological factors and waste, in and out of the tissue. Here, we have successfully designed and printed a series of novel 3D bone scaffolds with both bone formation supporting structures and highly interconnected 3D microvascular mimicking channels, for efficient and enhanced osteogenic bone regeneration as well as vascular cell growth. Using a chemical functionalization process, we have conjugated our samples with nano hydroxyapatite (nHA), for the creation of novel micro and nano featured devices for vascularized bone growth. We evaluated our scaffolds with mechanical testing, hydrodynamic measurements and in vitro human mesenchymal stem cell (hMSC) adhesion (4 h), proliferation (1, 3 and 5 d) and osteogenic differentiation (1, 2 and 3 weeks). These tests confirmed bone-like physical properties and vascular-like flow profiles, as well as demonstrated enhanced hMSC adhesion, proliferation and osteogenic differentiation. Additional in vitro experiments with human umbilical vein endothelial cells also demonstrated improved vascular cell growth, migration and organization on micro-nano featured scaffolds.

  10. 3D and Education

    Meulien Ohlmann, Odile

    2013-02-01

    Today the industry offers a chain of 3D products. Learning to "read" and to "create in 3D" becomes an issue of education of primary importance. 25 years professional experience in France, the United States and Germany, Odile Meulien set up a personal method of initiation to 3D creation that entails the spatial/temporal experience of the holographic visual. She will present some different tools and techniques used for this learning, their advantages and disadvantages, programs and issues of educational policies, constraints and expectations related to the development of new techniques for 3D imaging. Although the creation of display holograms is very much reduced compared to the creation of the 90ies, the holographic concept is spreading in all scientific, social, and artistic activities of our present time. She will also raise many questions: What means 3D? Is it communication? Is it perception? How the seeing and none seeing is interferes? What else has to be taken in consideration to communicate in 3D? How to handle the non visible relations of moving objects with subjects? Does this transform our model of exchange with others? What kind of interaction this has with our everyday life? Then come more practical questions: How to learn creating 3D visualization, to learn 3D grammar, 3D language, 3D thinking? What for? At what level? In which matter? for whom?

  11. Comprehensive evaluation of high-steep slope stability and optimal high-steep slope design by 3D physical modeling

    Xing-ping Lai; Peng-fei Shan; Mei-feng Cai; Fen-hua Ren; Wen-hui Tan

    2015-01-01

    High-steep slope stability and its optimal excavation design in Shuichang open pit iron mine were analyzed based on a large 3D physical simulation technique. An optimal excavation scheme with a relatively steeper slope angle was successfully implemented at the northwest wall between Nos. 4 and 5 exploration lines of Shuichang Iron Mine, taking into account the 3D scale effect. The phys-ico-mechanical properties of rock materials were obtained by laboratory tests conducted on sample cores from exploration drilling directly from the iron mine. A porous rock-like composite material was formed for the model, and the mechanical parameters of the material were assessed experimentally;specifically, the effect of water on the sample was quantitatively determined. We adopted an experimental setup using stiff modular applied static loading to carry out a visual excavation of the slope at a random depth. The setup was equipped with acous-tic emission (AE) sensors, and the experiments were monitored by crack optical acquirement, ground penetrating radar, and close-field pho-togrammetry to investigate the mechanisms of rock-mass destabilization in the high-steep slope. For the complex study area, the model re-sults indicated a clear correlation between the model’s destabilization resulting from slope excavation and the collected monitoring informa-tion. During the model simulation, the overall angle of the slope increased by 1–6 degrees in different sections. Dramatically, the modeled excavation scheme saved over 80 million tons of rock from extraction, generating enormous economic and ecological benefits.

  12. Hydrothermal synthesis, structural elucidation, spectroscopic studies, thermal behavior and luminescence properties of a new 3-d compound: FeAlF2(C10H8N2)(HPO4)2(H2O)

    Bouzidia, Nabaa; Salah, Najet; Hamdi, Besma; Ben Salah, Abdelhamid

    2017-04-01

    The study of metal phosphate has been a proactive field of research thanks to its applied and scientific importance, especially in terms of the development of optical devices such as solid state lasers as well as optical fibers. The present paper seeks to investigate the synthesis, crystal structure, elemental analysis and properties of FeAlF2(C10H8N2)(HPO4)2(H2O) compound investigated by spectroscopic studies (FT-IR and FT-Raman), thermal behavior and luminescence. The Hirshfeld surface analysis and 2-D fingerprint plot have been performed to explore the behavior of these weak interactions and crystal cohesion. This investigation shows that the molecules are connected by hydrogen bonds of the type Osbnd H⋯O and Osbnd H⋯F. In addition, the 2,2'‒bipyridine ligand plays a significant role in the construction of 3-D supramolecular framework via π‒π stacking. FT‒IR and FT‒Raman spectra were used so as to ease the responsibilities of the vibration modes of the title compound. The thermal analysis (TGA) study shows a mass loss evolution as a temperature function. Finally, the optical properties were evaluated by photoluminescence spectroscopy.

  13. Synthesis, activity evaluation and 3D-QSAR study of some novel derivatives of 4, 5, 6, 7-tetrahydrothieno [3,2-c] pyridine

    Die Cheng; Deng Ke Liu; Mo Liu; Ying Liu; Wei Ren Xu; Chang Xiao Liu

    2008-01-01

    A series of novel derivatives of 4, 5, 6, 7-tetrahydrothieno [3,2-c] pyridine were synthesized and strucmrally characterized by 1H NMR and MS. Their in vivo anti-platelet aggregation activities were evaluated. A 3D-QSAR was performed using the CoMFA and the CoMSIA. This model provided useful guidelines for novel anti-platelet thienopyridines design.

  14. VIRTUAL ANTI-BULLYING VILLAGE PROJECT FOR COPING WITH BULLYING AND CYBERBULLYING WITHIN A 3D VIRTUAL LEARNING ENVIRONMENT: EVALUATION RESEARCH

    Dorit Olenik Shemesh; Tali Heiman, Eyal Rabin

    2014-01-01

    The current study aims to evaluate the implementation of a unique educational project- The Virtual Anti-Bullying Village for Kids and Teens (ABV4KIDS) that was designed and operated by the European Commission. A 3D virtual environment as an innovative, international project for adolescents, focused on knowledge acquisition and new ways of coping with bullying and cyberbullying. Sixty seventh graders-Israeli adolescents-completed five questionnaires before and after the project to assess its i...

  15. Role of biplane digital subtraction angiography, and 3D rotational angiography in craniopagus twins: A case report, detailed pictorial evaluation, and review of literature.

    Sudha, Lakshmi; Dev, Bhawna; Kamble, Ravindra; Joseph, Santhosh

    2009-07-01

    Cranially conjoined twins (craniopagus) are regarded as one of the rarest human malformations. Craniopagus represents 2 to 6% of conjoined twins and is the rarest type of disorder. A conventional angiogram with three dimensions is needed to confirm the exact extent of sharing of the arterial / venous tree. 3D angiography was first proposed by CORNELIUS and advanced into clinical practice by VOIGT in 1975. We present a case of craniopagus vertical type II twins, evaluated for cerebral circulation.

  16. Role of biplane digital subtraction angiography, and 3D rotational angiography in craniopagus twins: A case report, detailed pictorial evaluation, and review of literature

    Lakshmi Sudha; Bhawna Dev; Ravindra Kamble; Santhosh Joseph

    2009-01-01

    Cranially conjoined twins (craniopagus) are regarded as one of the rarest human malformations. Craniopagus represents 2 to 6% of conjoined twins and is the rarest type of disorder. A conventional angiogram with three dimensions is needed to confirm the exact extent of sharing of the arterial / venous tree. 3D angiography was first proposed by CORNELIUS and advanced into clinical practice by VOIGT in 1975. We present a case of craniopagus vertical type II twins, evaluated for cerebral circulat...

  17. Role of biplane digital subtraction angiography, and 3D rotational angiography in craniopagus twins: A case report, detailed pictorial evaluation, and review of literature

    Lakshmi Sudha

    2009-01-01

    Full Text Available Cranially conjoined twins (craniopagus are regarded as one of the rarest human malformations. Craniopagus represents 2 to 6% of conjoined twins and is the rarest type of disorder. A conventional angiogram with three dimensions is needed to confirm the exact extent of sharing of the arterial / venous tree. 3D angiography was first proposed by CORNELIUS and advanced into clinical practice by VOIGT in 1975. We present a case of craniopagus vertical type II twins, evaluated for cerebral circulation.

  18. Evaluation of the use of laser scanning to create key models for 3D printing separate from and augmenting visible light sensing

    Straub, Jeremy; Kerlin, Scott

    2016-05-01

    The illicit creation of 3D printed keys is problematic as it can allow intruders nearly undetectable access to secure facilities. Prior work has discussed how keys can be created using visible light sensing. This paper builds on this work by evaluating the utility of keys produced with laser scanning. The quality of the model produced using a structured laser scanning approach is compared to the quality of a model produced using a similarly robust visible light sensing approach.

  19. The meaning and measurement of work fatigue: Development and evaluation of the Three-Dimensional Work Fatigue Inventory (3D-WFI).

    Frone, Michael R; Tidwell, Marie-Cecile O

    2015-07-01

    Although work fatigue represents an important construct in several substantive areas, prior conceptual definitions and measures have been inadequate in a number of ways. The goals of the present study were to develop a conceptual definition and outline the desirable characteristics of a work fatigue measure, briefly examine several prior measures of work fatigue-related constructs, and develop and evaluate a new measure of work fatigue. The Three-Dimensional Work Fatigue Inventory (3D-WFI) provides separate and commensurate assessments of physical, mental, and emotional work fatigue. Results from a pilot study (n = 207) and a broader evaluative study of U.S. wage and salary workers (n = 2,477) suggest that the 3D-WFI is psychometrically sound and evinces a meaningful pattern of relations with variables that comprise the nomological network of work fatigue. As with all new measures, additional research is required to evaluate fully the utility of the 3D-WFI in research on work fatigue.

  20. SU-C-213-05: Evaluation of a Composite Copper-Plastic Material for a 3D Printed Radiation Therapy Bolus

    Vitzthum, L; Ehler, E; Sterling, D; Reynolds, T; Higgins, P; Dusenbery, K [University of Minnesota, Minneapolis, MN (United States)

    2015-06-15

    Purpose: To evaluate a novel 3D printed bolus fabricated from a copper-plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques. Methods: Two models of bolus were created on a 3D printer using a composite copper-PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper-PLA/PHA plastic. Secondly, CT images of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams. Results: Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper-plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom. Conclusion: Sub-millimeter thickness, 3D printed composite copper-PLA/PHA bolus can provide a build-up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape. Funding provided by an intra-department grant of the University of Minnesota Department of Radiation Oncology.

  1. TEHNOLOGIJE 3D TISKALNIKOV

    Kolar, Nataša

    2016-01-01

    Diplomsko delo predstavi razvoj tiskanja skozi čas. Podrobneje so opisani 3D tiskalniki, ki uporabljajo različne tehnologije 3D tiskanja. Predstavljene so različne tehnologije 3D tiskanja, njihova uporaba in narejeni prototipi oz. končni izdelki. Diplomsko delo opiše celoten postopek, od zamisli, priprave podatkov in tiskalnika do izdelave prototipa oz. končnega izdelka.

  2. Mobile 3D television: development of core technological elements and user-centered evaluation methods toward an optimized system

    Gotchev, Atanas; Smolic, Aljoscha; Jumisko-Pyykkö, Satu; Strohmeier, Dominik; Bozdagi Akar, Gozde; Merkle, Philipp; Daskalov, Nikolai

    2009-02-01

    A European consortium of six partners has been developing core technological components of a mobile 3D television system over DVB-H channel. In this overview paper, we present our current results on developing optimal methods for stereo-video content creation, coding and transmission and emphasize their significance for the power-constrained mobile platform, equipped with auto-stereoscopic display. We address the user requirements by applying modern usercentered approaches taking into account different user groups and usage contexts in contrast to the laboratory assessment methods which, though standardized, offer limited applicability to real applications. To this end, we have been aiming at developing a methodological framework for the whole system development process. One of our goals has been to further develop the user-centered approach towards experienced quality of critical system components. In this paper, we classify different research methods and technological solutions analyzing their pros and constraints. Based on this analysis we present the user-centered methodological framework being used throughout the whole development process of the system and aimed at achieving the best performance and quality appealing to the end user.

  3. Systematical Evaluation of Mechanically Strong 3D Printed Diluted magnesium Doping Wollastonite Scaffolds on Osteogenic Capacity in Rabbit Calvarial Defects

    Sun, Miao; Liu, An; Shao, Huifeng; Yang, Xianyan; Ma, Chiyuan; Yan, Shigui; Liu, Yanming; He, Yong; Gou, Zhongru

    2016-01-01

    Wollastonite (CaSiO3; CSi) ceramic is a promising bioactive material for bone defect repair due to slightly fast degradation of its porous constructs in vivo. In our previous strategy some key features of CSi ceramic have been significantly improved by dilute magnesium doping for regulating mechanical properties and biodegradation. Here we demonstrate that 6 ~ 14% of Ca substituted by Mg in CSi (CSi-Mgx, x = 6, 10, 14) can enhance the mechanical strength (>40 MPa) but not compromise biological performances of the 3D printed porous scaffolds with open porosity of 60‒63%. The in vitro cell culture tests in vitro indicated that the dilute Mg doping into CSi was beneficial for ALP activity and high expression of osteogenic marker genes of MC3T3-E1 cells in the scaffolds. A good bone tissue regeneration response and elastoplastic response in mechanical strength in vivo were determined after implantation in rabbit calvarial defects for 6‒12 weeks. Particularly, the CSi-Mg10 and CSi-Mg14 scaffolds could enhance new bone regeneration with a significant increase of newly formed bone tissue (18 ~ 22%) compared to the pure CSi (~14%) at 12 weeks post-implantation. It is reasonable to consider that, therefore, such CSi-Mgx scaffolds possessing excellent strength and reasonable degradability are promising for bone reconstruction in thin-wall bone defects. PMID:27658481

  4. Evaluation of the combined effects of target size, respiratory motion and background activity on 3D and 4D PET/CT images

    Park, Sang-June; Ionascu, Dan; Killoran, Joseph; Chin, Lee; Berbeco, Ross [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115 (United States); Mamede, Marcelo; Gerbaudo, Victor H [Division of Nuclear Medicine, Department of Radiology, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA 02115 (United States)], E-mail: spark@lroc.harvard.edu

    2008-07-07

    Gated (4D) PET/CT has the potential to greatly improve the accuracy of radiotherapy at treatment sites where internal organ motion is significant. However, the best methodology for applying 4D-PET/CT to target definition is not currently well established. With the goal of better understanding how to best apply 4D information to radiotherapy, initial studies were performed to investigate the effect of target size, respiratory motion and target-to-background activity concentration ratio (TBR) on 3D (ungated) and 4D PET images. Using a PET/CT scanner with 4D or gating capability, a full 3D-PET scan corrected with a 3D attenuation map from 3D-CT scan and a respiratory gated (4D) PET scan corrected with corresponding attenuation maps from 4D-CT were performed by imaging spherical targets (0.5-26.5 mL) filled with {sup 18}F-FDG in a dynamic thorax phantom and NEMA IEC body phantom at different TBRs (infinite, 8 and 4). To simulate respiratory motion, the phantoms were driven sinusoidally in the superior-inferior direction with amplitudes of 0, 1 and 2 cm and a period of 4.5 s. Recovery coefficients were determined on PET images. In addition, gating methods using different numbers of gating bins (1-20 bins) were evaluated with image noise and temporal resolution. For evaluation, volume recovery coefficient, signal-to-noise ratio and contrast-to-noise ratio were calculated as a function of the number of gating bins. Moreover, the optimum thresholds which give accurate moving target volumes were obtained for 3D and 4D images. The partial volume effect and signal loss in the 3D-PET images due to the limited PET resolution and the respiratory motion, respectively were measured. The results show that signal loss depends on both the amplitude and pattern of respiratory motion. However, the 4D-PET successfully recovers most of the loss induced by the respiratory motion. The 5-bin gating method gives the best temporal resolution with acceptable image noise. The results based on

  5. Histological evaluation of osteogenesis of 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds in a rabbit model

    Ge Zigang; Tian Xianfeng; Heng, Boon Chin; Fan, Victor; Yeo Jinfei; Cao Tong, E-mail: omscaot@nus.edu.s [Stem Cell Laboratory, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074 (Singapore)

    2009-04-15

    Utilizing a suitable combination of lactide and glycolide in a copolymer would optimize the degradation rate of a scaffold upon implantation in situ. Moreover, 3D printing technology enables customizing the shape of the scaffold to biometric data from CT and MRI scans. A previous in vitro study has shown that novel 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds had good biocompatibility and mechanical properties comparable with human cancellous bone, while they could support proliferation and osteogenic differentiation of osteoblasts. Based on the previous study, this study evaluated PLGA scaffolds for bone regeneration within a rabbit model. The scaffolds were implanted at two sites on the same animal, within the periosteum and within bi-cortical bone defects on the iliac crest. Subsequently, the efficacy of bone regeneration within the implanted scaffolds was evaluated at 4, 12 and 24 weeks post-surgery through histological analysis. In both the intra-periosteum and iliac bone defect models, the implanted scaffolds facilitated new bone tissue formation and maturation over the time course of 24 weeks, even though there was initially observed to be little tissue ingrowth within the scaffolds at 4 weeks post-surgery. Hence, the 3D-printed porous PLGA scaffolds investigated in this study displayed good biocompatibility and are osteoconductive in both the intra-periosteum and iliac bone defect models. (communication)

  6. Novel substituted benzothiophene and thienothiophene carboxanilides and quinolones: synthesis, photochemical synthesis, DNA-binding properties, antitumor evaluation and 3D-derived QSAR analysis.

    Aleksić, Maja; Bertoša, Branimir; Nhili, Raja; Uzelac, Lidija; Jarak, Ivana; Depauw, Sabine; David-Cordonnier, Marie-Hélène; Kralj, Marijeta; Tomić, Sanja; Karminski-Zamola, Grace

    2012-06-14

    A series of new N,N-dimethylaminopropyl- and 2-imidazolinyl-substituted derivatives of benzo[b]thienyl- and thieno[2,3-b]thienylcarboxanilides and benzo[b]thieno[2,3-c]- and thieno[3',2':4,5]thieno[2,3-c]quinolones were prepared. Quinolones were prepared by the reaction of photochemical dehydrohalogenation of corresponding anilides. Carboxanilides and quinolones were tested for the antiproliferative activity. 2-Imidazolinyl-substituted derivatives showed very prominent activity. By use of the experimentally obtained antitumor measurements, 3D-derived QSAR analysis was performed for the set of compounds. Highly predictive 3D-derived QSAR models were obtained, and molecular properties that have the highest impact on antitumor activity were identified. Carboxanilides 6a-c and quinolones 9a-c and 11a were evaluated for DNA binding propensities and topoisomerases I and II inhibition as part of their mechanism of action assessment. The evaluated differences in the mode of action nicely correlate with the results of the 3D-QSAR analysis. Taken together, the results indicate which modifications of the compounds from the series should further improve their anticancer properties.

  7. 3D Printable Graphene Composite.

    Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong

    2015-07-08

    In human being's history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today's personalization tide. New technology should be ushered in. Three-dimensional (3D) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be 3D printable into computer-designed models. The composite's linear thermal coefficient is below 75 ppm·°C(-1) from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process.

  8. Synthesis, 3D-QSAR analysis and biological evaluation of quinoxaline 1,4-di-N-oxide derivatives as antituberculosis agents.

    Pan, Yuanhu; Li, Panpan; Xie, Shuyu; Tao, Yanfei; Chen, Dongmei; Dai, Menghong; Hao, Haihong; Huang, Lingli; Wang, Yulian; Wang, Liye; Liu, Zhenli; Yuan, Zonghui

    2016-08-15

    A series of quinoxaline 1,4-di-N-oxide derivatives variously substituted at C-2 position were synthesized and evaluated for in vitro antimycobacterial activity. Seventeen compounds exhibited potential activity (MIC ⩽6.25μg/mL) against Mycobacterium tuberculosis (H37Rv), in particular the compounds 3d and 3j having an MIC value of 0.39μg/mL. None of the compounds exhibited cytotoxicity when using an MTT assay in VERO cells. To further investigate the structure-activity relationship, CoMFA (q(2)=0.507, r(2)=0.923) and CoMSIA (q(2)=0.665, r(2)=0.977) models were performed on the basis of antimycobacterial activity data. The 3D-QSAR study of these compounds can provide useful information for further rational design of novel quinoxaline 1,4-di-N-oxides for treatment of tuberculosis.

  9. Synthesis and in-vitro evaluation of 2-amino-4-arylthiazole as inhibitor of 3D polymerase against foot-and-mouth disease (FMD).

    Jeong, Kwi-Wan; Lee, Jung-Hun; Park, Sun-Mi; Choi, Joo-Hyung; Jeong, Dae-Youn; Choi, Dong-Hwa; Nam, Yeonju; Park, Jong-Hyeon; Lee, Kwang-Nyeong; Kim, Su-Mi; Ku, Jin-Mo

    2015-09-18

    Foot-and-mouth disease (FMD) is a highly contagious vesicular disease of livestock caused by a highly variable RNA virus, foot-and-mouth disease virus (FMDV). One of the targets to suppress expansion of and to control FMD is 3D polymerase (FMDV 3Dpol). In this study, 2-amino-4-arylthiazole derivatives were synthesized and evaluated for their inhibitory activity against FMDV 3Dpol. Among them, compound 20i exhibited the most potent functional inhibition (IC50 = 0.39 μM) of FMDV 3D polymerase and compound 24a (EC50 = 13.09 μM) showed more potent antiviral activity than ribavirin (EC50 = 1367 μM) and T1105 (EC50 = 347 μM) with IBRS-2 cells infected by the FMDV O/SKR/2010 strain.

  10. 3-D multiobservable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle. I: a priori petrological information and geophysical observables

    Afonso, J. C.; Fullea, J.; Griffin, W. L.; Yang, Y.; Jones, A. G.; D. Connolly, J. A.; O'Reilly, S. Y.

    2013-05-01

    of natural mantle samples collected from different tectonic settings (xenoliths, abyssal peridotites, ophiolite samples, etc.). This strategy relaxes more typical and restrictive assumptions such as the use of local/limited xenolith data or compositional regionalizations based on age-composition relations. We demonstrate that the combination of our ρ(m) with a L(m) that exploits the differential sensitivities of specific geophysical observables provides a general and robust inference platform to address the thermochemical structure of the lithosphere and sublithospheric upper mantle. An accompanying paper deals with the integration of these two functions into a general 3-D multiobservable Bayesian inversion method and its computational implementation.

  11. Medical 3D thermography system

    GRUBIŠIĆ, IVAN

    2011-01-01

    Infrared (IR) thermography determines the surface temperature of an object or human body using thermal IR measurement camera. It is an imaging technology which is contactless and completely non-invasive. These propertiesmake IR thermography a useful method of analysis that is used in various industrial applications to detect, monitor and predict irregularities in many fields from engineering to medical and biological observations. This paper presents a conceptual model of Medical 3D Thermo...

  12. 3D virtuel udstilling

    Tournay, Bruno; Rüdiger, Bjarne

    2006-01-01

    3d digital model af Arkitektskolens gård med virtuel udstilling af afgangsprojekter fra afgangen sommer 2006. 10 s.......3d digital model af Arkitektskolens gård med virtuel udstilling af afgangsprojekter fra afgangen sommer 2006. 10 s....

  13. Development, evaluation and application of 3D QSAR Pharmacophore model in the discovery of potential human renin inhibitors

    John Shalini

    2011-12-01

    Full Text Available Abstract Background Renin has become an attractive target in controlling hypertension because of the high specificity towards its only substrate, angiotensinogen. The conversion of angiotensinogen to angiotensin I is the first and rate-limiting step of renin-angiotensin system and thus designing inhibitors to block this step is focused in this study. Methods Ligand-based quantitative pharmacophore modeling methodology was used in identifying the important molecular chemical features present in the set of already known active compounds and the missing features from the set of inactive compounds. A training set containing 18 compounds including active and inactive compounds with a substantial degree of diversity was used in developing the pharmacophore models. A test set containing 93 compounds, Fischer randomization, and leave-one-out methods were used in the validation of the pharmacophore model. Database screening was performed using the best pharmacophore model as a 3D structural query. Molecular docking and density functional theory calculations were used to select the hit compounds with strong molecular interactions and favorable electronic features. Results The best quantitative pharmacophore model selected was made of one hydrophobic, one hydrogen bond donor, and two hydrogen bond acceptor features with high a correlation value of 0.944. Upon validation using an external test set of 93 compounds, Fischer randomization, and leave-one-out methods, this model was used in database screening to identify chemical compounds containing the identified pharmacophoric features. Molecular docking and density functional theory studies have confirmed that the identified hits possess the essential binding characteristics and electronic properties of potent inhibitors. Conclusion A quantitative pharmacophore model of predictive ability was developed with essential molecular features of a potent renin inhibitor. Using this pharmacophore model, two

  14. Objective 3D surface evaluation of intracranial electrophysiologic correlates of cerebral glucose metabolic abnormalities in children with focal epilepsy.

    Jeong, Jeong-Won; Asano, Eishi; Kumar Pilli, Vinod; Nakai, Yasuo; Chugani, Harry T; Juhász, Csaba

    2017-03-21

    To determine the spatial relationship between 2-deoxy-2[(18) F]fluoro-D-glucose (FDG) metabolic and intracranial electrophysiological abnormalities in children undergoing two-stage epilepsy surgery, statistical parametric mapping (SPM) was used to correlate hypo- and hypermetabolic cortical regions with ictal and interictal electrocorticography (ECoG) changes mapped onto the brain surface. Preoperative FDG-PET scans of 37 children with intractable epilepsy (31 with non-localizing MRI) were compared with age-matched pseudo-normal pediatric control PET data. Hypo-/hypermetabolic maps were transformed to 3D-MRI brain surface to compare the locations of metabolic changes with electrode coordinates of the ECoG-defined seizure onset zone (SOZ) and interictal spiking. While hypometabolic clusters showed a good agreement with the SOZ on the lobar level (sensitivity/specificity = 0.74/0.64), detailed surface-distance analysis demonstrated that large portions of ECoG-defined SOZ and interictal spiking area were located at least 3 cm beyond hypometabolic regions with the same statistical threshold (sensitivity/specificity = 0.18-0.25/0.94-0.90 for overlap 3-cm distance); for a lower threshold, sensitivity for SOZ at 3 cm increased to 0.39 with a modest compromise of specificity. Performance of FDG-PET SPM was slightly better in children with smaller as compared with widespread SOZ. The results demonstrate that SPM utilizing age-matched pseudocontrols can reliably detect the lobe of seizure onset. However, the spatial mismatch between metabolic and EEG epileptiform abnormalities indicates that a more complete SOZ detection could be achieved by extending intracranial electrode coverage at least 3 cm beyond the metabolic abnormality. Considering that the extent of feasible electrode coverage is limited, localization information from other modalities is particularly important to optimize grid coverage in cases of large hypometabolic cortex. Hum Brain Mapp, 2017. © 2017

  15. Deterministic evaluation of collapse risk for a decomissioned flooded mine system: 3D numerical modelling of subsidence, roof collapse and impulse water flow.

    Castellanza, Riccardo; Fernandez Merodo, Josè Antonio; di Prisco, Claudio; Frigerio, Gabriele; Crosta, Giovanni B.; Orlandi, Gianmarco

    2013-04-01

    Aim of the study is the assessment of stability conditions for an abandoned gypsum mine (Bologna , Italy). Mining was carried out til the end of the 70s by the room and pillar method. During mining a karst cave was crossed karstic waters flowed into the mine. As a consequence, the lower level of the mining is completely flooded and portions of the mining levels show critical conditions and are structurally prone to instability. Buildings and infrastructures are located above the first and second level and a large portion of the area below the mine area, and just above of the Savena river, is urbanised. Gypsum geomechanical properties change over time; water, or even air humidity, dissolves or weaken gypsum pillars, leading progressively to collapse. The mine is located in macro-crystalline gypsum beds belonging to the Messinian Gessoso Solfifera Formation. Selenitic gypsum beds are interlayered with by centimetre to meter thick shales layers. In order to evaluate the risk related to the collapse of the flooded level (level 3) a deterministic approach based on 3D numerical analyses has been considered. The entire abandoned mine system up to the ground surface has been generated in 3D. The considered critical scenario implies the collapse of the pillars and roof of the flooded level 3. In a first step, a sequential collapse starting from the most critical pillar has been simulated by means of a 3D Finite Element code. This allowed the definition of the subsidence basin at the ground surface and the interaction with the buildings in terms of ground displacements. 3D numerical analyses have been performed with an elasto-perfectly plastic constitutive model. In a second step, the effect of a simultaneous collapse of the entire level 3 has been considered in order to evaluate the risk of a flooding due to the water outflow from the mine system. Using a 3D CFD (Continuum Fluid Dynamics) finite element code the collapse of the level 3 has been simulated and the volume of

  16. Intraoperative evaluation of device placement in spine surgery using known-component 3D-2D image registration.

    Uneri, A; De Silva, T; Goerres, J; Jacobson, M W; Ketcha, M D; Reaungamornrat, S; Kleinszig, G; Vogt, S; Khanna, A J; Osgood, G M; Wolinsky, J-P; Siewerdsen, J H

    2017-04-21

    Intraoperative x-ray radiography/fluoroscopy is commonly used to assess the placement of surgical devices in the operating room (e.g. spine pedicle screws), but qualitative interpretation can fail to reliably detect suboptimal delivery and/or breach of adjacent critical structures. We present a 3D-2D image registration method wherein intraoperative radiographs are leveraged in combination with prior knowledge of the patient and surgical components for quantitative assessment of device placement and more rigorous quality assurance (QA) of the surgical product. The algorithm is based on known-component registration (KC-Reg) in which patient-specific preoperative CT and parametric component models are used. The registration performs optimization of gradient similarity, removes the need for offline geometric calibration of the C-arm, and simultaneously solves for multiple component bodies, thereby allowing QA in a single step (e.g. spinal construct with 4-20 screws). Performance was tested in a spine phantom, and first clinical results are reported for QA of transpedicle screws delivered in a patient undergoing thoracolumbar spine surgery. Simultaneous registration of ten pedicle screws (five contralateral pairs) demonstrated mean target registration error (TRE) of 1.1  ±  0.1 mm at the screw tip and 0.7  ±  0.4° in angulation when a prior geometric calibration was used. The calibration-free formulation, with the aid of component collision constraints, achieved TRE of 1.4  ±  0.6 mm. In all cases, a statistically significant improvement (p  <  0.05) was observed for the simultaneous solutions in comparison to previously reported sequential solution of individual components. Initial application in clinical data in spine surgery demonstrated TRE of 2.7  ±  2.6 mm and 1.5  ±  0.8°. The KC-Reg algorithm offers an independent check and quantitative QA of the surgical product using radiographic/fluoroscopic views

  17. Evaluation of expansion algorithm of measurement range suited for 3D shape measurement using two pitches of projected grating with light source-stepping method

    Sakaguchi, Toshimasa; Fujigaki, Motoharu; Murata, Yorinobu

    2015-03-01

    Accurate and wide-range shape measurement method is required in industrial field. The same technique is possible to be used for a shape measurement of a human body for the garment industry. Compact 3D shape measurement equipment is also required for embedding in the inspection system. A shape measurement by a phase shifting method can measure the shape with high spatial resolution because the coordinates can be obtained pixel by pixel. A key-device to develop compact equipment is a grating projector. Authors developed a linear LED projector and proposed a light source stepping method (LSSM) using the linear LED projector. The shape measurement euipment can be produced with low-cost and compact without any phase-shifting mechanical systems by using this method. Also it enables us to measure 3D shape in very short time by switching the light sources quickly. A phase unwrapping method is necessary to widen the measurement range with constant accuracy for phase shifting method. A general phase unwrapping method with difference grating pitches is often used. It is one of a simple phase unwrapping method. It is, however, difficult to apply the conventional phase unwrapping algorithm to the LSSM. Authors, therefore, developed an expansion unwrapping algorithm for the LSSM. In this paper, an expansion algorithm of measurement range suited for 3D shape measurement using two pitches of projected grating with the LSSM was evaluated.

  18. Gebiss: an ImageJ plugin for the specification of ground truth and the performance evaluation of 3d segmentation algorithms

    Yee Kwo

    2011-06-01

    Full Text Available Abstract Background Image segmentation is a crucial step in quantitative microscopy that helps to define regions of tissues, cells or subcellular compartments. Depending on the degree of user interactions, segmentation methods can be divided into manual, automated or semi-automated approaches. 3D image stacks usually require automated methods due to their large number of optical sections. However, certain applications benefit from manual or semi-automated approaches. Scenarios include the quantification of 3D images with poor signal-to-noise ratios or the generation of so-called ground truth segmentations that are used to evaluate the accuracy of automated segmentation methods. Results We have developed Gebiss; an ImageJ plugin for the interactive segmentation, visualisation and quantification of 3D microscopic image stacks. We integrated a variety of existing plugins for threshold-based segmentation and volume visualisation. Conclusions We demonstrate the application of Gebiss to the segmentation of nuclei in live Drosophila embryos and the quantification of neurodegeneration in Drosophila larval brains. Gebiss was developed as a cross-platform ImageJ plugin and is freely available on the web at http://imaging.bii.a-star.edu.sg/projects/gebiss/.

  19. Human Thermal Model Evaluation Using the JSC Human Thermal Database

    Bue, Grant; Makinen, Janice; Cognata, Thomas

    2012-01-01

    Human thermal modeling has considerable long term utility to human space flight. Such models provide a tool to predict crew survivability in support of vehicle design and to evaluate crew response in untested space environments. It is to the benefit of any such model not only to collect relevant experimental data to correlate it against, but also to maintain an experimental standard or benchmark for future development in a readily and rapidly searchable and software accessible format. The Human thermal database project is intended to do just so; to collect relevant data from literature and experimentation and to store the data in a database structure for immediate and future use as a benchmark to judge human thermal models against, in identifying model strengths and weakness, to support model development and improve correlation, and to statistically quantify a model s predictive quality. The human thermal database developed at the Johnson Space Center (JSC) is intended to evaluate a set of widely used human thermal models. This set includes the Wissler human thermal model, a model that has been widely used to predict the human thermoregulatory response to a variety of cold and hot environments. These models are statistically compared to the current database, which contains experiments of human subjects primarily in air from a literature survey ranging between 1953 and 2004 and from a suited experiment recently performed by the authors, for a quantitative study of relative strength and predictive quality of the models.

  20. Blender 3D cookbook

    Valenza, Enrico

    2015-01-01

    This book is aimed at the professionals that already have good 3D CGI experience with commercial packages and have now decided to try the open source Blender and want to experiment with something more complex than the average tutorials on the web. However, it's also aimed at the intermediate Blender users who simply want to go some steps further.It's taken for granted that you already know how to move inside the Blender interface, that you already have 3D modeling knowledge, and also that of basic 3D modeling and rendering concepts, for example, edge-loops, n-gons, or samples. In any case, it'

  1. Postoperative Radiotherapy for Prostate Cancer: A Comparison of Four Consensus Guidelines and Dosimetric Evaluation of 3D-CRT Versus Tomotherapy IMRT

    Malone, Shawn, E-mail: smalone@ottawahospital.on.ca [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Croke, Jennifer [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Roustan-Delatour, Nicolas; Belanger, Eric [Department of Pathology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Avruch, Leonard [Department of Radiology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Malone, Colin [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Morash, Christopher [Division of Urology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Kayser, Cathleen; Underhill, Kathryn; Li Yan; Malone, Kyle [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Nyiri, Balazs [Department of Medical Physics, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Spaans, Johanna [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)

    2012-11-01

    Purpose: Despite the benefits of adjuvant radiotherapy after radical prostatectomy, approximately one-half of patients relapse. Four consensus guidelines have been published (European Organization for Research and Treatment of Cancer, Faculty of Radiation Oncology Genito-Urinary Group, Princess Margaret Hospital, Radiation Therapy Oncology Group) with the aim of standardizing the clinical target volume (CTV) delineation and improve outcomes. To date, no attempt has been made to compare these guidelines in terms of treatment volumes or organ at risk (OAR) irradiation. The extent to which the guideline-derived plans meet the dosimetric constraints of present trials or of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) trial is also unknown. Our study also explored the dosimetric benefits of intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 20 patients treated with postoperative RT were included. The three-dimensional conformal radiotherapy (3D-CRT) plans were applied to cover the guideline-generated planning target volumes (66 Gy in 33 fractions). Dose-volume histograms (DVHs) were analyzed for CTV/planning target volume coverage and to evaluate OAR irradiation. The OAR DVHs were compared with the constraints proposed in the QUANTEC and Radiotherapy and Androgen Deprivation In Combination After Local Surgery (RADICALS) trials. 3D-CRT plans were compared with the tomotherapy plans for the Radiation Therapy Oncology Group planning target volume to evaluate the advantages of IMRT. Results: The CTV differed significantly between guidelines (p < 0.001). The European Organization for Research and Treatment of Cancer-CTVs were significantly smaller than the other CTVs (p < 0.001). Differences in prostate bed coverage superiorly accounted for the major volumetric differences between the guidelines. Using 3D-CRT, the DVHs rarely met the QUANTEC or RADICALS rectal constraints, independent of the guideline used. The RADICALS

  2. Use of combined Hartree–Fock–Roothaan theory in evaluation of lowest states of $K[Ar]4s^0 3d^1$ and $Cr^+ [Ar]4s^0 3d^5$ isoelectronic series over noninteger -Slater type orbitals

    I I Guseinov; M Erturk; E Sahin

    2011-01-01

    By using noninteger n-Slater type orbitals in combined Hartree–Fock–Roothaan method, self-consistent field calculations of orbital and lowest states energies have been performed for the isoelectronic series of open shell systems $K[Ar]4s^0 3d^1 ({}^2D) (Z = 19–30)$ and $Cr^+[Ar]4s^0 3d^5 ({}^6 S) (Z = 24–30)$. The results of the calculations for the orbital and total energies obtained by using minimal basis-sets of noninteger -Slater type orbitals are given in the tables. The results are compared with the extended-basis Hartree–Fock computations. The orbital and total energies are in good agreement with those presented in the literature. The results can be useful in the study of various properties of heavy atomic systems when the combined Hartree–Fock–Roothaan approach is employed.

  3. Evaluation of the Convergence Region of an Automated Registration Method for 3D Laser Scanner Point Clouds.

    Bae, Kwang-Ho

    2009-01-01

    Using three dimensional point clouds from both simulated and real datasets from close and terrestrial laser scanners, the rotational and translational convergence regions of Geometric Primitive Iterative Closest Points (GP-ICP) are empirically evaluated. The results demonstrate the GP-ICP has a larger rotational convergence region than the existing methods, e.g., the Iterative Closest Point (ICP).

  4. A systematic method for using 3D echocardiography to evaluate tricuspid valve insufficiency in hypoplastic left heart syndrome

    Christopher Robin Mart

    2014-01-01

    We have proposed a systematic method for evaluating and displaying the TV using 3DE which can provide significant insight into the mechanisms causing TVI in HLHS. This has the potential to improve both the surgical approach to repairing the valve and, ultimately, patient outcomes.

  5. 3D Digital Modelling

    Hundebøl, Jesper

    wave of new building information modelling tools demands further investigation, not least because of industry representatives' somewhat coarse parlance: Now the word is spreading -3D digital modelling is nothing less than a revolution, a shift of paradigm, a new alphabet... Research qeustions. Based...... on empirical probes (interviews, observations, written inscriptions) within the Danish construction industry this paper explores the organizational and managerial dynamics of 3D Digital Modelling. The paper intends to - Illustrate how the network of (non-)human actors engaged in the promotion (and arrest) of 3......D Modelling (in Denmark) stabilizes - Examine how 3D Modelling manifests itself in the early design phases of a construction project with a view to discuss the effects hereof for i.a. the management of the building process. Structure. The paper introduces a few, basic methodological concepts...

  6. Professional Papervision3D

    Lively, Michael

    2010-01-01

    Professional Papervision3D describes how Papervision3D works and how real world applications are built, with a clear look at essential topics such as building websites and games, creating virtual tours, and Adobe's Flash 10. Readers learn important techniques through hands-on applications, and build on those skills as the book progresses. The companion website contains all code examples, video step-by-step explanations, and a collada repository.

  7. AE3D

    2016-06-20

    AE3D solves for the shear Alfven eigenmodes and eigenfrequencies in a torodal magnetic fusion confinement device. The configuration can be either 2D (e.g. tokamak, reversed field pinch) or 3D (e.g. stellarator, helical reversed field pinch, tokamak with ripple). The equations solved are based on a reduced MHD model and sound wave coupling effects are not currently included.

  8. Methods for Evaluating Thermal Camouflage

    2005-12-01

    conduction in a vehicle will cause a heat flow from for instance a warm engine to the outer surfaces of the vehicle. The heat will also spread over the...longer possible to identify the vehicle, and in (e) it can only be detected as a blob . If confusing objects are introduced to the background it becomes...Current industry criteria for thermal imaging systems (after Holst (1)) Task Description # Cycles Detection The blob has a reasonable probability of

  9. 3D Evaluation of the Lamina Cribrosa with Swept-Source Optical Coherence Tomography in Normal Tension Glaucoma

    Kazuko Omodaka; Takaaki Horii; Seri Takahashi; Tsutomu Kikawa; Akiko Matsumoto; Yukihiro Shiga; Kazuichi Maruyama; Tetsuya Yuasa; Masahiro Akiba; Toru Nakazawa

    2015-01-01

    Purpose Although the lamina cribrosa (LC) is the primary site of axonal damage in glaucoma, adequate methods to image and measure it are currently lacking. Here, we describe a noninvasive, in vivo method of evaluating the LC, based on swept-source optical coherence tomography (SS-OCT), and determine this method’s ability to quantify LC thickness. Methods This study comprised 54 eyes, including normal (n = 18), preperimetric glaucoma (PPG; n = 18), and normal tension glaucoma (NTG; n = 18) eye...

  10. INFFTM: Fast evaluation of 3d Fourier series in MATLAB with an application to quantum vortex reconnections

    Caliari, Marco; Zuccher, Simone

    2017-04-01

    Although Fourier series approximation is ubiquitous in computational physics owing to the Fast Fourier Transform (FFT) algorithm, efficient techniques for the fast evaluation of a three-dimensional truncated Fourier series at a set of arbitrary points are quite rare, especially in MATLAB language. Here we employ the Nonequispaced Fast Fourier Transform (NFFT, by J. Keiner, S. Kunis, and D. Potts), a C library designed for this purpose, and provide a Matlab® and GNU Octave interface that makes NFFT easily available to the Numerical Analysis community. We test the effectiveness of our package in the framework of quantum vortex reconnections, where pseudospectral Fourier methods are commonly used and local high resolution is required in the post-processing stage. We show that the efficient evaluation of a truncated Fourier series at arbitrary points provides excellent results at a computational cost much smaller than carrying out a numerical simulation of the problem on a sufficiently fine regular grid that can reproduce comparable details of the reconnecting vortices.

  11. Description of an evaluation system for knee kinematics in ligament lesions, by means of optical tracking and 3D tomography,

    Tiago Lazzaretti Fernandes

    2014-10-01

    Full Text Available Objective:To describe and demonstrate the viability of a method for evaluating knee kine matics, by means of a continuous passive motion (CPM machine, before and after anterio cruciate ligament (ACL injury.Methods:This study was conducted on a knee from a cadaver, in a mechanical pivot-shif simulator, with evaluations using optical tracking, and also using computed tomography.Results:This study demonstrated the viability of a protocol for measuring the rotation an translation of the knee, using reproducible and objective tools (error<0.2mm. The mech anized provocation system of the pivot-shift test was independent of the examiner an always allowed the same angular velocity and traction of 20 N throughout the movement.Conclusion:The clinical relevance of this method lies in making inferences about the in viv behavior of a knee with an ACL injury and providing greater methodological quality in futur studies for measuring surgical techniques with grafts in relatively close positions.

  12. Thermally activated 3D to 2D structural transformation of [Ni{sub 2}(en){sub 2}(H{sub 2}O){sub 6}(pyr)]·4H{sub 2}O flexible coordination polymer

    Begović, Nebojša N. [Faculty of Physical Chemistry, University of Belgrade (Serbia); Institute of General and Physical Chemistry, Belgrade (Serbia); Blagojević, Vladimir A. [Faculty of Physical Chemistry, University of Belgrade (Serbia); Ostojić, Sanja B.; Radulović, Aleksandra M. [Institute of General and Physical Chemistry, Belgrade (Serbia); Poleti, Dejan [Faculty of Technology and Metallurgy, University of Belgrade (Serbia); Minić, Dragica M., E-mail: dminic@ffh.bg.ac.rs [Faculty of Physical Chemistry, University of Belgrade (Serbia); Department of Biomedical Sciences, State University of Novi Pazar (Serbia)

    2015-01-15

    Thermally activated 3D to 2D structural transformation of the binuclear [Ni{sub 2}(en){sub 2}(H{sub 2}O){sub 6}(pyr)]·4H{sub 2}O complex was investigated using a combination of theoretical and experimental methods. Step-wise thermal degradation (dehydration followed by release of ethylene diamine) results in two layered flexible coordination polymer structures. Dehydration process around 365 K results in a conjugated 2D structure with weak interlayer connectivity. It was shown to be a reversible 3D to 2D framework transformation by a guest molecule, and rehydration of the dehydration product occurs at room temperature in saturated water vapor. Rehydrated complex exhibits lower dehydration temperature, due to decreased average crystalline size, with higher surface area resulting in easier release and diffusion of water during dehydration. Thermal degradation of dehydration around 570 K, results in loss of ethylene diamine, producing a related 2D layered polymer structure, without interconnectivity between individual polymer layers. - Highlights: • Reversible 3D to 2D framework topochemical transformation on dehydration around 365 K. • Resulting polymer exhibits 2D layered structure with weak interlayer connectivity. • Dehydration is fully reversible in saturated water vapor at room temperature. • Further degradation around 570 K yields 2D polymer without interlayer connectivity. • 2D polymer exhibits conjugated electronic system.

  13. Dosimetric evaluation of a commercial 3D treatment planning system using the AAPM Task Group 23 test package.

    Casanova Borca, Valeria; Pasquino, Massimo; Bresciani, Sara; Catuzzo, Paola; Ozzello, Franca; Tofani, Santi

    2005-03-01

    The accuracy of the dose calculation algorithm is one of the most critical steps in assessing the radiotherapy treatment to achieve the 5% accuracy in dose delivery, which represents the suggested limit to increase the complication-free local control of tumor. We have used the AAPM Task Group 23 (TG-23) test package for clinical photon external beam therapy to evaluate the accuracy of the new version of the PLATO TPS algorithm. The comparison between tabulated values and calculated ones has been performed for 266 and 297 dose values for the 4 and 18 MV photon beams, respectively. Dose deviations less than 2% were found in the 98.5%- and 90.6% analyzed dose points for the two considered energies, respectively. Larger deviations were obtained for both energies, in large dose gradients, such as the build-up region or near the field edges and blocks. As far as the radiological field width is concerned, 64 points were analyzed for both the energies: 53 points (83%) and 64 points (100%) were within +/-2 millimeters for the 4 and 18 MV photon beams, respectively. The results show the good accuracy of the algorithm either in simple geometry beam conditions or in complex ones, in homogeneous medium, and in the presence of inhomogeneities, for low and high energy beams. Our results fit well the data reported by several authors related to the calculation accuracy of different treatment planning systems (TPSs) (within a mean value of 0.7% and 1.2% for 4 and 18 MV respectively). The TG-23 test package can be considered a powerful instrument to evaluate dose calculation accuracy, and as such may play an important role in a quality assurance program related to the commissioning of a new TPS.

  14. Simulation of at-sensor radiance over land for proposed thermal channels of Imager payload onboard INSAT-3D satellite using MODTRAN model

    M R Pandya; D B Shah; H J Trivedi; S Panigrahy

    2011-02-01

    INSAT-3D is the new generation Indian satellite designed for improved Earth observations through two payloads – Imager and Sounder. Study was conducted with an aim of simulating satellite level signal over land in the infrared channels of the Imager payload using a radiative transfer model MODTRAN. Satellite level at-sensor radiance corresponding to all four infrared channels of INSAT-3D Imager payload is obtained using MODTRAN and sensitivity of at-sensor radiance was inferred as a function of input parameters namely, surface temperature, emissivity, view angle and atmospheric water vapour, which is helpful in understanding the signal simulation scheme needed for retrieving a very critical parameter namely, land surface temperature.

  15. Investigation of feedback on neutron kinetics and thermal hydraulics from detailed online fuel behavior modeling during a boron dilution transient in a PWR with the two-way coupled code system DYN3D-TRANSURANUS

    Holt, L., E-mail: lars.holt@tuev-sued.de [TÜV SÜD Energietechnik GmbH Baden-Württemberg, Gottlieb-Daimler-Str. 7, 70794 Filderstadt (Germany); Technical University München, Department of Nuclear Engineering, Boltzmannstr. 15, D-85748 Garching bei München (Germany); Rohde, U.; Kliem, S.; Baier, S. [Helmholtz-Zentrum Dresden—Rossendorf, Reactor Safety Division, PO Box 510119, D-01314 Dresden (Germany); Seidl, M. [E.ON Kernkraft GmbH, Tresckowstr. 5, D-30457 Hannover (Germany); Van Uffelen, P. [European Commission, Joint Research Centre, Institute for Transuranium Elements, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Macián-Juan, R. [Technical University München, Department of Nuclear Engineering, Boltzmannstr. 15, D-85748 Garching bei München (Germany)

    2016-02-15

    Highlights: • General coupling interface was developed for the fuel performance code TRANSURANUS. • With this new tool simplified fuel behavior models in codes can be replaced. • The reactor dynamics code DYN3D was coupled to TRANSURANUS at assembly level. • The feedback from detailed online fuel behavior modeling is analyzed for reactivity initiated accident (RIA). • The thermal hydraulics can be affected strongly even in fresh fuel assemblies. - Abstract: Recently the reactor dynamics code DYN3D (including an internal fuel behavior model) was coupled to the fuel performance code TRANSURANUS at assembly level. The coupled code system applies the new general TRANSURANUS coupling interface, hence it can be used for one-way or two-way coupling. In the coupling, DYN3D provides process time, time-dependent rod power and thermal hydraulics conditions to TRANSURANUS, which in case of the two-way coupling approach replaces completely the internal DYN3D fuel behavior model and transfers parameters like radial fuel temperature distribution and cladding temperature back to DYN3D. For the first time results of the coupled code system are presented for a post-critical-heat-flux heat transfer. The corresponding heat transfer regime is mostly film boiling, where the cladding temperature can rise several hundreds of degrees. The simulated boron dilution transient assumed an injection of a 36 m{sup 3} slug of under-borated coolant into a German pressurized water reactor (PWR) core initiated from a sub-critical reactor state (extreme reactivity initiated accident (RIA) conditions). The feedback from detailed fuel behavior modeling was found negligible on the neutron kinetics and thermal hydraulics during the first power rise. In a later phase of the transient, the node injected energy can differ 25 J/g, even still around 20 J/g for nodes without film boiling. Furthermore, the thermal hydraulics can be affected strongly even in fresh fuel assemblies, where film boiling

  16. Comparative evaluation of the accuracy of linear measurements between cone beam computed tomography and 3D microtomography

    Francesca Mangione

    2013-09-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the influence of artifacts on the accuracy of linear measurements estimated with a common cone beam computed tomography (CBCT system used in dental clinical practice, by comparing it with microCT system as standard reference. MATERIALS AND METHODS: Ten bovine bone cylindrical samples containing one implant each, able to provide both points of reference and image quality degradation, have been scanned by CBCT and microCT systems. Thanks to the software of the two systems, for each cylindrical sample, two diameters taken at different levels, by using implants different points as references, have been measured. Results have been analyzed by ANOVA and a significant statistically difference has been found. RESULTS AND DISCUSSION: Due to the obtained results, in this work it is possible to say that the measurements made with the two different instruments are still not statistically comparable, although in some samples were obtained similar performances and therefore not statistically significant. CONCLUSION: With the improvement of the hardware and software of CBCT systems, in the near future the two instruments will be able to provide similar performances.

  17. Evaluating a 3-D transport model of atmospheric CO2 using ground-based, aircraft, and space-borne data

    J.-D. Paris

    2010-07-01

    Full Text Available We evaluate the GEOS-Chem atmospheric transport model (v8-02-01 of CO2 over 2003–2006, driven by GEOS-4 and GEOS-5 meteorology from the NASA Goddard Global Modelling and Assimilation Office, using surface, aircraft and space-borne concentration measurements of CO2. We use an established ensemble Kalman filter to estimate a posteriori biospheric+biomass burning (BS+BB and oceanic (OC CO2 fluxes from 22 geographical regions, following the TransCom 3 protocol, using boundary layer CO2 data from a subset of GLOBALVIEW surface sites. Global annual net BS+BB+OC CO2 fluxes over 2004–2006 for GEOS-4 (GEOS-5 meteorology are −4.4±0.9 (−4.2±0.9, −3.9±0.9 (−4.5±0.9, and −5.2±0.9 (−4.9±0.9 Pg C yr−1 , respectively. The regional a posteriori fluxes are broadly consistent in the sign and magnitude of the TransCom-3 study for 1992–1996, but we find larger net sinks over northern and southern continents. We find large departures from our a priori over Europe during summer 2003, over temperate Eurasia during 2004, and over North America during 2005, reflecting an incomplete description of terrestrial carbon dynamics. We find GEOS-4 (GEOS-5 a posteriori CO2 concentrations reproduce the observed surface trend of 1.91–2.43 ppm yr−1, depending on latitude, within 0.15 ppm yr−1 (0.2 ppm yr−1 and the seasonal cycle within 0.2 ppm (0.2 ppm at all latitudes. We find the a posteriori model reproduces the aircraft vertical profile measurements of CO2 over North America and Siberia generally within 1.5 ppm in the free and upper troposphere but can be biased by up to 4–5 ppm in the boundary layer at the start and end of the growing season. The model has a small negative bias in the free troposphere CO2 trend (1.95–2.19 ppm yr−1 compared to AIRS data which has a trend of 2.21–2.63 ppm yr−1 during 2004–2006, consistent with surface data. Model CO2 concentrations in the upper troposphere, evaluated using CONTRAIL (Comprehensive

  18. Evaluating a 3-D transport model of atmospheric CO2 using ground-based, aircraft, and space-borne data

    J.-D. Paris

    2011-03-01

    Full Text Available We evaluate the GEOS-Chem atmospheric transport model (v8-02-01 of CO2 over 2003–2006, driven by GEOS-4 and GEOS-5 meteorology from the NASA Goddard Global Modeling and Assimilation Office, using surface, aircraft and space-borne concentration measurements of CO2. We use an established ensemble Kalman Filter to estimate a posteriori biospheric+biomass burning (BS + BB and oceanic (OC CO2 fluxes from 22 geographical regions, following the TransCom-3 protocol, using boundary layer CO2 data from a subset of GLOBALVIEW surface sites. Global annual net BS + BB + OC CO2 fluxes over 2004–2006 for GEOS-4 (GEOS-5 meteorology are −4.4 ± 0.9 (−4.2 ± 0.9, −3.9 ± 0.9 (−4.5 ± 0.9, and −5.2 ± 0.9 (−4.9 ± 0.9 PgC yr−1, respectively. After taking into account anthropogenic fossil fuel and bio-fuel emissions, the global annual net CO2 emissions for 2004–2006 are estimated to be 4.0 ± 0.9 (4.2 ± 0.9, 4.8 ± 0.9 (4.2 ± 0.9, and 3.8 ± 0.9 (4.1 ± 0.9 PgC yr−1, respectively. The estimated 3-yr total net emission for GEOS-4 (GEOS-5 meteorology is equal to 12.5 (12.4 PgC, agreeing with other recent top-down estimates (12–13 PgC. The regional a posteriori fluxes are broadly consistent in the sign and magnitude of the TransCom-3 study for 1992–1996, but we find larger net sinks over northern and southern continents. We find large departures from our a priori over Europe during summer 2003, over temperate Eurasia during 2004, and over North America during 2005, reflecting an incomplete description of terrestrial carbon dynamics. We find GEOS-4 (GEOS-5 a posteriori CO2 concentrations reproduce the observed surface trend of 1.91–2.43 ppm yr−1 (parts per million per year, depending on latitude, within 0.15 ppm yr−1 (0.2 ppm yr−1 and the seasonal cycle within 0.2 ppm (0.2 ppm at all latitudes. We find the a posteriori model reproduces the aircraft vertical profile measurements of CO2 over North America and Siberia generally within 1

  19. Evaluation of the effective corneal ablation in refractive surgery by two 3D topographic surface matching methods

    Bueeler, M.; Donitzky, Ch.; Mrochen, M.

    2006-02-01

    The effectiveness of the corneal ablation process in refractive surgery is mostly evaluated by indirect measures of vision or optical quality such as post-operative refraction or wavefront aberrometry. Yet, the effective amount of corneal tissue removed in the treatment can only be determined by correctly overlapping a pre- and a post-operative topography measurement. However such an overlap is not trivial due to the discrepancy in the centration axes used in the measurement and the treatment, as well as due to the shift of ocular axes through the treatment or tilt between the two surfaces. We therefore present two methods for overlapping pre- and post-operative topographies for the purpose of extracting an effective corneal ablation profile. Method one uses a 3-dimensional profile matching algorithm and cross-correlation analysis on surface rings outside the optical zone of the topographies. Method two employs a surface normal matching routine to align the two surfaces along their common ablation axis. The profile matching method implies the problem that it requires measurement data outside of the optical zone which was found to be uncertain with placido-disk-based topographers. Method number two is more simple and implies the advantage of using measurement data within the optical zone. For regular profiles the extracted ablation profiles showed a very good match with the planned ones. Surprisingly, even for highly irregular profiles of topography-guided laser treatments the method delivered reasonable overlaps when being compared to the planned profiles. Analysis of the effective tissue removal yields valuable information on the quality of the ablation process.

  20. 3D Spectroscopic Instrumentation

    Bershady, Matthew A

    2009-01-01

    In this Chapter we review the challenges of, and opportunities for, 3D spectroscopy, and how these have lead to new and different approaches to sampling astronomical information. We describe and categorize existing instruments on 4m and 10m telescopes. Our primary focus is on grating-dispersed spectrographs. We discuss how to optimize dispersive elements, such as VPH gratings, to achieve adequate spectral resolution, high throughput, and efficient data packing to maximize spatial sampling for 3D spectroscopy. We review and compare the various coupling methods that make these spectrographs ``3D,'' including fibers, lenslets, slicers, and filtered multi-slits. We also describe Fabry-Perot and spatial-heterodyne interferometers, pointing out their advantages as field-widened systems relative to conventional, grating-dispersed spectrographs. We explore the parameter space all these instruments sample, highlighting regimes open for exploitation. Present instruments provide a foil for future development. We give an...

  1. 3D Projection Installations

    Halskov, Kim; Johansen, Stine Liv; Bach Mikkelsen, Michelle

    2014-01-01

    Three-dimensional projection installations are particular kinds of augmented spaces in which a digital 3-D model is projected onto a physical three-dimensional object, thereby fusing the digital content and the physical object. Based on interaction design research and media studies, this article...... contributes to the understanding of the distinctive characteristics of such a new medium, and identifies three strategies for designing 3-D projection installations: establishing space; interplay between the digital and the physical; and transformation of materiality. The principal empirical case, From...... Fingerplan to Loop City, is a 3-D projection installation presenting the history and future of city planning for the Copenhagen area in Denmark. The installation was presented as part of the 12th Architecture Biennale in Venice in 2010....

  2. Evaluation of the reliability of the maximum entropy method for reconstructing 3D and 4D NOESY-type NMR spectra of proteins.

    Shigemitsu, Yoshiki; Ikeya, Teppei; Yamamoto, Akihiro; Tsuchie, Yuusuke; Mishima, Masaki; Smith, Brian O; Güntert, Peter; Ito, Yutaka

    2015-02-06

    Despite their advantages in analysis, 4D NMR experiments are still infrequently used as a routine tool in protein NMR projects due to the long duration of the measurement and limited digital resolution. Recently, new acquisition techniques for speeding up multidimensional NMR experiments, such as nonlinear sampling, in combination with non-Fourier transform data processing methods have been proposed to be beneficial for 4D NMR experiments. Maximum entropy (MaxEnt) methods have been utilised for reconstructing nonlinearly sampled multi-dimensional NMR data. However, the artefacts arising from MaxEnt processing, particularly, in NOESY spectra have not yet been clearly assessed in comparison with other methods, such as quantitative maximum entropy, multidimensional decomposition, and compressed sensing. We compared MaxEnt with other methods in reconstructing 3D NOESY data acquired with variously reduced sparse sampling schedules and found that MaxEnt is robust, quick and competitive with other methods. Next, nonlinear sampling and MaxEnt processing were applied to 4D NOESY experiments, and the effect of the artefacts of MaxEnt was evaluated by calculating 3D structures from the NOE-derived distance restraints. Our results demonstrated that sufficiently converged and accurate structures (RMSD of 0.91Å to the mean and 1.36Å to the reference structures) were obtained even with NOESY spectra reconstructed from 1.6% randomly selected sampling points for indirect dimensions. This suggests that 3D MaxEnt processing in combination with nonlinear sampling schedules is still a useful and advantageous option for rapid acquisition of high-resolution 4D NOESY spectra of proteins.

  3. VIRTUAL ANTI-BULLYING VILLAGE PROJECT FOR COPING WITH BULLYING AND CYBERBULLYING WITHIN A 3D VIRTUAL LEARNING ENVIRONMENT: EVALUATION RESEARCH

    Dorit Olenik Shemesh

    2014-12-01

    Full Text Available The current study aims to evaluate the implementation of a unique educational project- The Virtual Anti-Bullying Village for Kids and Teens (ABV4KIDS that was designed and operated by the European Commission. A 3D virtual environment as an innovative, international project for adolescents, focused on knowledge acquisition and new ways of coping with bullying and cyberbullying. Sixty seventh graders-Israeli adolescents-completed five questionnaires before and after the project to assess its impacts regarding cyberbullying and socio-emotional variables. They evaluated the project as important, enjoyable, and increasing their knowledge about cyberbullying, but expressed a need for more practical tools for coping. At the end of the project, the control group reported more cyberbullying experiences, as well as a decrease in social support, whereas the research group reported no changes in cyberbullying experiences and in socio-emotional aspects.

  4. Interaktiv 3D design

    Villaume, René Domine; Ørstrup, Finn Rude

    2002-01-01

    Projektet undersøger potentialet for interaktiv 3D design via Internettet. Arkitekt Jørn Utzons projekt til Espansiva blev udviklet som et byggesystem med det mål, at kunne skabe mangfoldige planmuligheder og mangfoldige facade- og rumudformninger. Systemets bygningskomponenter er digitaliseret som...... 3D elementer og gjort tilgængelige. Via Internettet er det nu muligt at sammenstille og afprøve en uendelig  række bygningstyper som  systemet blev tænkt og udviklet til....

  5. Evaluation of New Thermally Conductive Geopolymer in Thermal Energy Storage

    Černý, Matěj; Uhlík, Jan; Nosek, Jaroslav; Lachman, Vladimír; Hladký, Radim; Franěk, Jan; Brož, Milan

    This paper describes an evaluation of a newly developed thermally conductive geopolymer (TCG), consisting of a mixture of sodium silicate and carbon micro-particles. The TCG is intended to be used as a component of high temperature energy storage (HTTES) to improve its thermal diffusivity. Energy storage is crucial for both ecological and economical sustainability. HTTES plays a vital role in solar energy technologies and in waste heat recovery. The most advanced HTTES technologies are based on phase change materials or molten salts, but suffer with economic and technological limitations. Rock or concrete HTTES are cheaper, but they have low thermal conductivity without incorporation of TCG. It was observed that TCG is stable up to 400 °C. The thermal conductivity was measured in range of 20-23 W m-1 K-1. The effect of TCG was tested by heating a granite block with an artificial fissure. One half of the fissure was filled with TCG and the other with ballotini. 28 thermometers, 5 dilatometers and strain sensors were installed on the block. The heat transport experiment was evaluated with COMSOL Multiphysics software.

  6. Quantitative 3D ultrashort time-to-echo (UTE) MRI and micro-CT (μCT) evaluation of the temporomandibular joint (TMJ) condylar morphology

    Geiger, Daniel [Sapienza University of Rome, Department of Radiological, Oncological and Pathological Sciences, Rome (Italy); Bae, Won C.; Statum, Sheronda; Du, Jiang; Chung, Christine B. [University of California-San Diego, Department of Radiology, San Diego, CA (United States)

    2014-01-15

    Temporomandibular dysfunction involves osteoarthritis of the TMJ, including degeneration and morphologic changes of the mandibular condyle. The purpose of this study was to determine the accuracy of novel 3D-UTE MRI versus micro-CT (μCT) for quantitative evaluation of mandibular condyle morphology. Nine TMJ condyle specimens were harvested from cadavers (2 M, 3 F; age 85 ± 10 years, mean ± SD). 3D-UTE MRI (TR = 50 ms, TE = 0.05 ms, 104-μm isotropic-voxel) was performed using a 3-T MR scanner and μCT (18-μm isotropic-voxel) was also performed. MR datasets were spatially registered with a μCT dataset. Two observers segmented bony contours of the condyles. Fibrocartilage was segmented on the MR dataset. Using a custom program, bone and fibrocartilage surface coordinates, Gaussian curvature, volume of segmented regions, and fibrocartilage thickness were determined for quantitative evaluation of joint morphology. Agreement between techniques (MRI vs. μCT) and observers (MRI vs. MRI) for Gaussian curvature, mean curvature, and segmented volume of the bone were determined using intraclass correlation coefficient (ICC) analysis. Between MRI and μCT, the average deviation of surface coordinates was 0.19 ± 0.15 mm, slightly higher than the spatial resolution of MRI. Average deviation of the Gaussian curvature and volume of segmented regions, from MRI to μCT, was 5.7 ± 6.5 % and 6.6 ± 6.2 %, respectively. ICC coefficients (MRI vs. μCT) for Gaussian curvature, mean curvature, and segmented volumes were 0.892, 0.893, and 0.972, respectively. Between observers (MRI vs. MRI), the ICC coefficients were 0.998, 0.999, and 0.997, respectively. Fibrocartilage thickness was 0.55 ± 0.11 mm, as previously described in the literature for grossly normal TMJ samples. 3D-UTE MR quantitative evaluation of TMJ condyle morphology ex-vivo, including surface, curvature, and segmented volume, shows high correlation against μCT and between observers. In addition, UTE MRI allows

  7. Adolescent patient with bilateral crossbite treated with surgically assisted rapid maxillary expansion: a case report evaluated by the 3d laser scanner, and using FESA method.

    Ivanov, Ch I; Velemínská, J; Dostálová, T; Foltán, R

    2011-01-01

    Our purpose in this case report is to present an orthodontic treatment obtained and the results achieved in 17-year-old white female patient with Angle Class II malocclusion and bilateral posterior crossbite. Patient was treated with bonded acrylic Hyrax appliance and surgically assisted rapid maxillary expansion (SARME). The multiloop system 0.16 TMA (ß titanium) arch wire was used in the alignment phase and on purpose to prohibit bite opening and optimize threedimensional movement control. After treatment bonded lingual retainers were placed in between maxillary central incisors and in mandible canine-to-canine. A functional removable Klammt appliance was used for retention. The 3D Laser Scanner Roland LPX-250 was used in order to obtain digital dental casts. Evaluation of the treatment results was measured on these models and using finite element scaling analysis (FESA). An Angle Class I relationship was obtained after 2½ years of treatment, function and facial aesthetics were improved. The shape of the palate changed significant in the width direction, not significantly in length and high direction. The greatest expansion of palate was found in the region between the palatal cusps of the first molars 26.6%, followed by first 21.9% and second premolars 16.5%. SARME in adult patients with bilateral cross bite and maxillary deficiency lead to satisfactory results. The 3D laser scanned models and their measurements, using advanced software's are successfully used for precise studies.

  8. Tangible 3D Modelling

    Hejlesen, Aske K.; Ovesen, Nis

    2012-01-01

    This paper presents an experimental approach to teaching 3D modelling techniques in an Industrial Design programme. The approach includes the use of tangible free form models as tools for improving the overall learning. The paper is based on lecturer and student experiences obtained through...

  9. 3D Wire 2015

    Jordi, Moréton; F, Escribano; J. L., Farias

    This document is a general report on the implementation of gamification in 3D Wire 2015 event. As the second gamification experience in this event, we have delved deeply in the previous objectives (attracting public areas less frequented exhibition in previous years and enhance networking) and ha......, improves socialization and networking, improves media impact, improves fun factor and improves encouragement of the production team....

  10. Motion-capture-based walking simulation of digital human adapted to laser-scanned 3D as-is environments for accessibility evaluation

    Tsubasa Maruyama

    2016-07-01

    Full Text Available Owing to our rapidly aging society, accessibility evaluation to enhance the ease and safety of access to indoor and outdoor environments for the elderly and disabled is increasing in importance. Accessibility must be assessed not only from the general standard aspect but also in terms of physical and cognitive friendliness for users of different ages, genders, and abilities. Meanwhile, human behavior simulation has been progressing in the areas of crowd behavior analysis and emergency evacuation planning. However, in human behavior simulation, environment models represent only “as-planned” situations. In addition, a pedestrian model cannot generate the detailed articulated movements of various people of different ages and genders in the simulation. Therefore, the final goal of this research was to develop a virtual accessibility evaluation by combining realistic human behavior simulation using a digital human model (DHM with “as-is” environment models. To achieve this goal, we developed an algorithm for generating human-like DHM walking motions, adapting its strides, turning angles, and footprints to laser-scanned 3D as-is environments including slopes and stairs. The DHM motion was generated based only on a motion-capture (MoCap data for flat walking. Our implementation constructed as-is 3D environment models from laser-scanned point clouds of real environments and enabled a DHM to walk autonomously in various environment models. The difference in joint angles between the DHM and MoCap data was evaluated. Demonstrations of our environment modeling and walking simulation in indoor and outdoor environments including corridors, slopes, and stairs are illustrated in this study.

  11. Solar Thermal System Evaluation in China

    Xinyu Zhang

    2015-01-01

    Full Text Available More than 581 solar thermal systems (STSs, 98 counties, and 47 renewable application demonstration cites in China need to be inspected by the end of 2015. In this study, the baseline for performance and economic evaluation of STSs are presented based on the site test data and related references. An index used to evaluate STSs was selected, and methods to acquire the parameters used to calculate the related index were set. The requirements for sensors for testing were specified. The evaluation method was applied to three systems and the result shows that the evaluation method is suitable for the evaluation of STSs in China.

  12. 3D medical thermography device

    Moghadam, Peyman

    2015-05-01

    In this paper, a novel handheld 3D medical thermography system is introduced. The proposed system consists of a thermal-infrared camera, a color camera and a depth camera rigidly attached in close proximity and mounted on an ergonomic handle. As a practitioner holding the device smoothly moves it around the human body parts, the proposed system generates and builds up a precise 3D thermogram model by incorporating information from each new measurement in real-time. The data is acquired in motion, thus it provides multiple points of view. When processed, these multiple points of view are adaptively combined by taking into account the reliability of each individual measurement which can vary due to a variety of factors such as angle of incidence, distance between the device and the subject and environmental sensor data or other factors influencing a confidence of the thermal-infrared data when captured. Finally, several case studies are presented to support the usability and performance of the proposed system.

  13. 3D Printable Graphene Composite

    Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong

    2015-07-01

    In human being’s history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today’s personalization tide. New technology should be ushered in. Three-dimensional (3D) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be 3D printable into computer-designed models. The composite’s linear thermal coefficient is below 75 ppm·°C-1 from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process.

  14. The Extended-OPQ Method for User-Centered Quality of Experience Evaluation: A Study for Mobile 3D Video Broadcasting over DVB-H

    Jumisko-Pyykkö Satu

    2011-01-01

    Full Text Available Abstract The Open Profiling of Quality (OPQ is a mixed methods approach combining a conventional quantitative psychoperceptual evaluation and qualitative descriptive quality evaluation based on naïve participants' individual vocabulary. The method targets evaluation of heterogeneous and multimodal stimulus material. The current OPQ data collection procedure provides a rich pool of data, but full benefit of it has neither been taken in the analysis to build up completeness in understanding the phenomenon under the study nor has the procedure in the analysis been probed with alternative methods. The goal of this paper is to extend the original OPQ method with advanced research methods that have become popular in related research and the component model to be able to generalize individual attributes into a terminology of Quality of Experience. We conduct an extensive subjective quality evaluation study for 3D video on mobile device with heterogeneous stimuli. We vary factors on content, media (coding, concealments, and slice modes, and transmission levels (channel loss rate. The results showed that advanced procedures in the analysis cannot only complement each other but also draw deeper understanding on Quality of Experience.

  15. 三维柔性触觉/热觉传感器设计与仿真%Design and simulation of 3 D flexible tactile/thermal sensor

    谢娜; 秦岚

    2015-01-01

    Aiming at difficult problem that current tactile sensor can not have both flexible,multi-dimensional force measurement and thermal perception and tactile signals mixed,design a flexible multi-fumction tactile/thermal sensor. Introduce basic structure of the sensor,and set up mathematical model three-dimensional force parallel measurement based on polyvinylidene fluoride( PVDF )film properties. Tactile detection based on piezoelectric effect of PVDF and thermal detection based on pyroelectric effect of PVDF. Gy doing proportional subtraction on tactile and thermal sensing signal,completely distinguish tactile and thermal sensing signals.%针对目前触觉传感器研究中不能兼有柔韧性、多维力测量和热觉与触觉信号混杂等难题,设计了一种柔性多功能触觉/热觉传感器。介绍了该传感器的基本结构,并基于聚偏氟乙烯( PVDF)薄膜的特性建立了三维力并行测量的数学模型。触觉检测基于PVDF的压电效应,热觉检测基于PVDF的热释电效应。通过对触觉和热觉信号做比例减法运算,从而彻底区分触觉和热觉信号。

  16. Self-assembled 3D heterometallic Cu(II)/Fe(II) coordination polymers with octahedral net skeletons: structural features, molecular magnetism, thermal and oxidation catalytic properties.

    Karabach, Yauhen Y; Guedes da Silva, M Fátima C; Kopylovich, Maximilian N; Gil-Hernández, Beatriz; Sanchiz, Joaquin; Kirillov, Alexander M; Pombeiro, Armando J L

    2010-12-06

    The new three-dimensional (3D) heterometallic Cu(II)/Fe(II) coordination polymers [Cu(6)(H(2)tea)(6)Fe(CN)(6)](n)(NO(3))(2n)·6nH(2)O (1) and [Cu(6)(Hmdea)(6)Fe(CN)(6)](n)(NO(3))(2n)·7nH(2)O (2) have been easily generated by aqueous-medium self-assembly reactions of copper(II) nitrate with triethanolamine or N-methyldiethanolamine (H(3)tea or H(2)mdea, respectively), in the presence of potassium ferricyanide and sodium hydroxide. They have been isolated as air-stable crystalline solids and fully characterized including by single-crystal X-ray diffraction analyses. The latter reveal the formation of 3D metal-organic frameworks that are constructed from the [Cu(2)(μ-H(2)tea)(2)](2+) or [Cu(2)(μ-Hmdea)(2)](2+) nodes and the octahedral [Fe(CN)(6)](4-) linkers, featuring regular (1) or distorted (2) octahedral net skeletons. Upon dehydration, both compounds show reversible escape and binding processes toward water or methanol molecules. Magnetic susceptibility measurements of 1 and 2 reveal strong antiferromagnetic [J = -199(1) cm(-1)] or strong ferromagnetic [J = +153(1) cm(-1)] couplings between the copper(II) ions through the μ-O-alkoxo atoms in 1 or 2, respectively. The differences in magnetic behavior are explained in terms of the dependence of the magnetic coupling constant on the Cu-O-Cu bridging angle. Compounds 1 and 2 also act as efficient catalyst precursors for the mild oxidation of cyclohexane by aqueous hydrogen peroxide to cyclohexanol and cyclohexanone (homogeneous catalytic system), leading to maximum total yields (based on cyclohexane) and turnover numbers (TONs) up to about 22% and 470, respectively.

  17. Unoriented 3d TFTs

    Bhardwaj, Lakshya

    2016-01-01

    This paper generalizes two facts about oriented 3d TFTs to the unoriented case. On one hand, it is known that oriented 3d TFTs having a topological boundary condition admit a state-sum construction known as the Turaev-Viro construction. This is related to the string-net construction of fermionic phases of matter. We show how Turaev-Viro construction can be generalized to unoriented 3d TFTs. On the other hand, it is known that the "fermionic" versions of oriented TFTs, known as Spin-TFTs, can be constructed in terms of "shadow" TFTs which are ordinary oriented TFTs with an anomalous Z_2 1-form symmetry. We generalize this correspondence to Pin+ TFTs by showing that they can be constructed in terms of ordinary unoriented TFTs with anomalous Z_2 1-form symmetry having a mixed anomaly with time-reversal symmetry. The corresponding Pin+ TFT does not have any anomaly for time-reversal symmetry however and hence it can be unambiguously defined on a non-orientable manifold. In case a Pin+ TFT admits a topological bou...

  18. Evaluation of Freehand B-Mode and Power-Mode 3D Ultrasound for Visualisation and Grading of Internal Carotid Artery Stenosis

    Karlas, Thomas; Saur, Dorothee

    2017-01-01

    Background Currently, colour-coded duplex sonography (2D-CDS) is clinical standard for detection and grading of internal carotid artery stenosis (ICAS). However, unlike angiographic imaging modalities, 2D-CDS assesses ICAS by its hemodynamic effects rather than luminal changes. Aim of this study was to evaluate freehand 3D ultrasound (3DUS) for direct visualisation and quantification of ICAS. Methods Thirty-seven patients with 43 ICAS were examined with 2D-CDS as reference standard and with freehand B-mode respectively power-mode 3DUS. Stenotic value of 3D reconstructed ICAS was calculated as distal diameter respectively distal cross-sectional area (CSA) reduction percentage and compared with 2D-CDS. Results There was a trend but no significant difference in successful 3D reconstruction of ICAS between B-mode and power mode (examiner 1 {Ex1} 81% versus 93%, examiner 2 {Ex2} 84% versus 88%). Inter-rater agreement was best for power-mode 3DUS and assessment of stenotic value as distal CSA reduction percentage (intraclass correlation coefficient {ICC} 0.90) followed by power-mode 3DUS and distal diameter reduction percentage (ICC 0.81). Inter-rater agreement was poor for B-mode 3DUS (ICC, distal CSA reduction 0.36, distal diameter reduction 0.51). Intra-rater agreement for power-mode 3DUS was good for both measuring methods (ICC, distal CSA reduction 0.88 {Ex1} and 0.78 {Ex2}; ICC, distal diameter reduction 0.83 {Ex1} and 0.76 {Ex2}). In comparison to 2D-CDS inter-method agreement was good and clearly better for power-mode 3DUS (ICC, distal diameter reduction percentage: Ex1 0.85, Ex2 0.78; distal CSA reduction percentage: Ex1 0.63, Ex2 0.57) than for B-mode 3DUS (ICC, distal diameter reduction percentage: Ex1 0.40, Ex2 0.52; distal CSA reduction percentage: Ex1 0.15, Ex2 0.51). Conclusions Non-invasive power-mode 3DUS is superior to B-mode 3DUS for imaging and quantification of ICAS. Thereby, further studies are warranted which should now compare power-mode 3DUS with

  19. Evaluation of anti-HER2 scFv-conjugated PLGA-PEG nanoparticles on 3D tumor spheroids of BT474 and HCT116 cancer cells

    Thuy Duong Le, Thi; Pham, Thu Hong; Nghia Nguyen, Trong; Giang Ngo, Thi Hong; Nhung Hoang, Thi My; Huan Le, Quang

    2016-06-01

    Three-dimensional culture cells (spheroids) are one of the multicellular culture models that can be applied to anticancer chemotherapeutic development. Multicellular spheroids more closely mimic in vivo tumor-like patterns of physiologic environment and morphology. In previous research, we designed docetaxel-loaded pegylated poly(D, L-lactide-co-glycolide) nanoparticles conjugated with anti-HER2 single chain antibodies (scFv-Doc-PLGA-PEG) and evaluated them in 2D cell culture. In this study, we continuously evaluate the cellular uptake and cytotoxic effect of scFv-Doc-PLGA-PEG on a 3D tumor spheroid model of BT474 (HER2-overexpressing) and HCT116 (HER2-underexpressing) cancer cells. The results showed that the nanoparticle formulation conjugated with scFv had a significant internalization effect on the spheroids of HER2-overexpressing cancer cells as compared to the spheroids of HER2-underexpressing cancer cells. Therefore, cytotoxic effects of targeted nanoparticles decreased the size and increased necrotic score of HER2-overexpressing tumor spheroids. Thus, these scFv-Doc-PLGA-PEG nanoparticles have potential for active targeting for HER2-overexpressing cancer therapy. In addition, BT474 and HCT116 spheroids can be used as a tumor model for evaluation of targeting therapies.

  20. Evaluation of the quantitative accuracy of 3D reconstruction of edentulous jaw models with jaw relation based on reference point system alignment.

    Weiwei Li

    Full Text Available OBJECTIVES: To apply contact measurement and reference point system (RPS alignment techniques to establish a method for 3D reconstruction of the edentulous jaw models with centric relation and to quantitatively evaluate its accuracy. METHODS: Upper and lower edentulous jaw models were clinically prepared, 10 pairs of resin cylinders with same size were adhered to axial surfaces of upper and lower models. The occlusal bases and the upper and lower jaw models were installed in the centric relation position. Faro Edge 1.8m was used to directly obtain center points of the base surface of the cylinders (contact method. Activity 880 dental scanner was used to obtain 3D data of the cylinders and the center points were fitted (fitting method. 3 pairs of center points were used to align the virtual model to centric relation. An observation coordinate system was interactively established. The straight-line distances in the X (horizontal left/right, Y (horizontal anterior/posterior, and Z (vertical between the remaining 7 pairs of center points derived from contact method and fitting method were measured respectively and analyzed using a paired t-test. RESULTS: The differences of the straight-line distances of the remaining 7 pairs of center points between the two methods were X: 0.074 ± 0.107 mm, Y: 0.168 ± 0.176 mm, and Z: -0.003± 0.155 mm. The results of paired t-test were X and Z: p >0.05, Y: p <0.05. CONCLUSION: By using contact measurement and the reference point system alignment technique, highly accurate reconstruction of the vertical distance and centric relation of a digital edentulous jaw model can be achieved, which meets the design and manufacturing requirements of the complete dentures. The error of horizontal anterior/posterior jaw relation was relatively large.

  1. The thermal structure and the location of the snow line in the protosolar nebula: axisymmetric models with full 3-D radiative transfer

    Min, M; Kama, M; Dominik, C

    2010-01-01

    The precise location of the water ice condensation front ('snow line') in the protosolar nebula has been a debate for a long time. Its importance stems from the expected substantial jump in the abundance of solids beyond the snow line, which is conducive to planet formation, and from the higher stickiness in collisions of ice-coated dust grains, which may help the process of coagulation of dust and the formation of planetesimals. In an optically thin nebula, the location of the snow line is easily calculated to be around 3 AU. However, in its first 5 to 10 million years, the solar nebula was optically thick, implying a smaller snow line radius due to shielding from direct sunlight, but also a larger radius because of viscous heating. Several models have attempted to treat these opposing effects. However, until recently treatments beyond an approximate 1+1D radiative transfer were unfeasible. We revisit the problem with a fully self-consistent 3D treatment in an axisymmetric disk model, including a density-dep...

  2. 3D and beyond

    Fung, Y. C.

    1995-05-01

    This conference on physiology and function covers a wide range of subjects, including the vasculature and blood flow, the flow of gas, water, and blood in the lung, the neurological structure and function, the modeling, and the motion and mechanics of organs. Many technologies are discussed. I believe that the list would include a robotic photographer, to hold the optical equipment in a precisely controlled way to obtain the images for the user. Why are 3D images needed? They are to achieve certain objectives through measurements of some objects. For example, in order to improve performance in sports or beauty of a person, we measure the form, dimensions, appearance, and movements.

  3. An aerial 3D printing test mission

    Hirsch, Michael; McGuire, Thomas; Parsons, Michael; Leake, Skye; Straub, Jeremy

    2016-05-01

    This paper provides an overview of an aerial 3D printing technology, its development and its testing. This technology is potentially useful in its own right. In addition, this work advances the development of a related in-space 3D printing technology. A series of aerial 3D printing test missions, used to test the aerial printing technology, are discussed. Through completing these test missions, the design for an in-space 3D printer may be advanced. The current design for the in-space 3D printer involves focusing thermal energy to heat an extrusion head and allow for the extrusion of molten print material. Plastics can be used as well as composites including metal, allowing for the extrusion of conductive material. A variety of experiments will be used to test this initial 3D printer design. High altitude balloons will be used to test the effects of microgravity on 3D printing, as well as parabolic flight tests. Zero pressure balloons can be used to test the effect of long 3D printing missions subjected to low temperatures. Vacuum chambers will be used to test 3D printing in a vacuum environment. The results will be used to adapt a current prototype of an in-space 3D printer. Then, a small scale prototype can be sent into low-Earth orbit as a 3-U cube satellite. With the ability to 3D print in space demonstrated, future missions can launch production hardware through which the sustainability and durability of structures in space will be greatly improved.

  4. Evaluation of the sensitivity of two 3D diode array dosimetry systems to setup error for quality assurance (QA) of volumetric-modulated arc therapy (VMAT).

    Li, Guangjun; Bai, Sen; Chen, Nianyong; Henderson, Lansdale; Wu, Kui; Xiao, Jianghong; Zhang, Yingjie; Jiang, Qingfeng; Jiang, Xiaoqin

    2013-09-06

    The purpose of this study is to evaluate the sensitivities of 3D diode arrays to setup error for patient-specific quality assurance (QA) of volumetric-modulated arc therapy (VMAT). Translational setup errors of ± 1, ± 2, and ± 3 mm in the RL, SI, and AP directions and rotational setup errors of ± 1° and ± 2° in the pitch, roll, and yaw directions were set up in two phantom systems, ArcCHECK and Delta4, with VMAT plans for 11 patients. Cone-beam computed tomography (CBCT) followed by automatic correction using a HexaPOD 6D treatment couch ensured the position accuracy. Dose distributions of the two phantoms were compared in order to evaluate the agreement between calculated and measured values by using γ analysis with 3%/3 mm, 3%/2 mm, and 2%/2 mm criteria. To determine the impact on setup error for VMAT QA, we evaluated the sensitivity of results acquired by both 3D diode array systems to setup errors in translation and rotation. For the VMAT QA of all patients, the pass rate with the 3%/3 mm criteria exceeded 95% using either phantom. For setup errors of 3 mm and 2°, respectively, the pass rates with the 3%/3mm criteria decreased by a maximum of 14.0% and 23.5% using ArcCHECK, and 14.4% and 5.0% using Delta4. Both systems are sensitive to setup error, and do not have mechanisms to account for setup errors in the software. The sensitivity of both VMAT QA systems was strongly dependent on the patient-specific plan. The sensitivity of ArcCHECK to the rotational error was higher than that of Delta4. In order to achieve less than 3% mean pass rate reduction of VMAT plan QA with the 3%/3 mm criteria, a setup accuracy of 2 mm/1° and 2 mm/2° is required for ArcCheck and Delta4 devices, respectively. The cumulative effect of the combined 2 mm translational and 1° rotational errors caused 3.8% and 2.4% mean pass rates reduction with 3%/3 mm criteria, respectively, for ArcCHECK and Delta4 systems. For QA of VMAT plans for nasopharyngeal cancer (NPC) using the Arc

  5. Microwave synthesis, spectral, thermal, 3D molecular modeling analysis and antimicrobial activities of some transition metal complexes of Schiff bases derived from 5-bromosalicylaldehyde

    Rajendra K. Jain

    2016-03-01

    Full Text Available The coordination complexes of Cr(III, Co(II, Ni(II and Cu(II derived from 5-bromosalicylidene-2-chloro-4-nitroaniline (HL1 and 5-bromosalicylidene-2-amino-5-chlorobenzophenone (HL2 have been synthesized by conventional as well as microwave methods. These compounds have been characterized by elemental analysis, FT-IR, FAB-mass, molar conductance, electronic spectra, 1H-NMR, ESR, magnetic susceptibility, electrical conductivity and thermal analyses. FAB-mass and thermal data show degradation pattern of the complexes. The thermal behavior of metal complexes shows that the hydrated complexes lose water molecules of hydration in the first step; followed by decomposition of ligand molecules in the subsequent steps. The computational studies of Cu(II complex of 5-bromosalicylidene-2-chloro-4-nitroaniline have also been done. Solid state electrical conductivity studies reflect the semiconducting nature of the complexes. The Schiff base and metal complexes show a good activity against the Gram-positive bacterium; Staphylococcus aureus and Gram-negative bacterium; Escherichia coli and fungi Aspergillus niger and Candida albicans.

  6. Simulation of A Main Steam Line Break Accident Using the Coupled 'System Thermal-Hydraulics, 3D reactor Kinetics, and Hot Channel' Analysis Capability of MARS 3.0

    Jeong, Jae Jun; Chung, Bub Dong

    2005-09-15

    For realistic analysis of thermal-hydraulics (T-H) transients in light water reactors, KAERI has developed the best-estimate T-H system code, MARS. The code has been improved from the consolidated version of the RELAP5/MOD3 and COBRA-TF codes. Then, the MARS code was coupled with a three-dimensional (3-D) reactor kinetics code, MASTER. This coupled calculation feature, in conjunction with the existing hot channel analysis capabilities of the MARS and MASTER codes, allows for more realistic simulations of nuclear system transients. In this work, a main steam line break (MSLB) accident is simulated using the coupled 'system T-H, 3-D reactor kinetics, and hot channel analysis' feature of the MARS code. Two coupled calculations are performed for demonstration. First, a coupled calculation of the 'system T-H and 3-D reactor kinetics' with a refined core T-H nodalization is carried out to obtain global core power and local departure from nucleate boiling (DNB) ratio (DNBR) behaviors. Next, for a more accurate DNBR prediction, another coupled calculation with subchannel meshes for the hot channels is performed. The results of the coupled calculations are very reasonable and consistent so that these can be used to remove the excessive conservatism in the conventional safety analysis.

  7. 3D Surgical Simulation

    Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael

    2009-01-01

    This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3D surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and 3D positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308

  8. TOWARDS: 3D INTERNET

    Ms. Swapnali R. Ghadge

    2013-08-01

    Full Text Available In today’s ever-shifting media landscape, it can be a complex task to find effective ways to reach your desired audience. As traditional media such as television continue to lose audience share, one venue in particular stands out for its ability to attract highly motivated audiences and for its tremendous growth potential the 3D Internet. The concept of '3D Internet' has recently come into the spotlight in the R&D arena, catching the attention of many people, and leading to a lot of discussions. Basically, one can look into this matter from a few different perspectives: visualization and representation of information, and creation and transportation of information, among others. All of them still constitute research challenges, as no products or services are yet available or foreseen for the near future. Nevertheless, one can try to envisage the directions that can be taken towards achieving this goal. People who take part in virtual worlds stay online longer with a heightened level of interest. To take advantage of that interest, diverse businesses and organizations have claimed an early stake in this fast-growing market. They include technology leaders such as IBM, Microsoft, and Cisco, companies such as BMW, Toyota, Circuit City, Coca Cola, and Calvin Klein, and scores of universities, including Harvard, Stanford and Penn State.

  9. Evaluation of errors set-up and setting margins calculation in treatments 3-D conformal radiotherapy; Evaluacion de errores de set-up y calculo de margenes de configuracion en tratamientos de radioterapia CONFORMADA 3-D

    Donis, S.; Robayna, B.; Gonzalez, A.; Hernandez Armas, J.

    2011-07-01

    The use of IGRT techniques provide knowledge of the mistakes made in the positioning of a patient, to population studies and estimate the margins for each population.In this paper we evaluate the errors of set-up in 3 different locations and from these margins are calculated configuration (SM).

  10. Evaluation of left atrial function by multidetector computed tomography before left atrial radiofrequency-catheter ablation: Comparison of a manual and automated 3D volume segmentation method

    Wolf, Florian, E-mail: florian.wolf@meduniwien.ac.a [Department of Radiology, Medical University of Vienna, Vienna (Austria); Ourednicek, Petr [Philips Medical Systems, Prague (Czech Republic); Loewe, Christian [Department of Radiology, Medical University of Vienna, Vienna (Austria); Richter, Bernhard; Goessinger, Heinz David; Gwechenberger, Marianne [Department of Cardiology, Medical University of Vienna, Vienna (Austria); Plank, Christina; Schernthaner, Ruediger Egbert; Toepker, Michael; Lammer, Johannes [Department of Radiology, Medical University of Vienna, Vienna (Austria); Feuchtner, Gudrun M. [Department of Radiology, Innsbruck Medical University, Innsbruck (Austria); Institute of Diagnostic Radiology, University Hospital Zurich (Switzerland)

    2010-08-15

    Introduction: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT). Methods and materials: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated. Results: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7 ml, 93 ml, 34.7 ml, 27.1% by the automated, and 122.7 ml, 89.9 ml, 32.8 ml, 26.3% by the manual method with no significant difference (p > 0.05) and high Pearsons correlation coefficients (r = 0.94, r = 0.94, r = 0.82 and r = 0.85, p < 0.0001), respectively. The automated method was significantly faster (p < 0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p < 0.0001). Conclusions: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.

  11. Imaging mesenchymal stem cells containing single wall nanotube nanoprobes in a 3D scaffold using photo-thermal optical coherence tomography

    Connolly, Emma; Subhash, Hrebesh M.; Leahy, Martin; Rooney, Niall; Barry, Frank; Murphy, Mary; Barron, Valerie

    2014-02-01

    Despite the fact, that a range of clinically viable imaging modalities, such as magnetic resonance imaging (MRI), computed tomography (CT), photo emission tomography (PET), ultrasound and bioluminescence imaging are being optimised to track cells in vivo, many of these techniques are subject to limitations such as the levels of contrast agent required, toxic effects of radiotracers, photo attenuation of tissue and backscatter. With the advent of nanotechnology, nanoprobes are leading the charge to overcome these limitations. In particular, single wall nanotubes (SWNT) have been shown to be taken up by cells and as such are effective nanoprobes for cell imaging. Consequently, the main aim of this research is to employ mesenchymal stem cells (MSC) containing SWNT nanoprobes to image cell distribution in a 3D scaffold for cartilage repair. To this end, MSC were cultured in the presence of 32μg/ml SWNT in cell culture medium (αMEM, 10% FBS, 1% penicillin/streptomycin) for 24 hours. Upon confirmation of cell viability, the MSC containing SWNT were encapsulated in hyaluronic acid gels and loaded on polylactic acid polycaprolactone scaffolds. After 28 days in complete chondrogenic medium, with medium changes every 2 days, chondrogenesis was confirmed by the presence of glycosaminoglycan. Moreover, using photothermal optical coherence tomography (PT-OCT), the cells were seen to be distributed through the scaffold with high resolution. In summary, these data reveal that MSC containing SWNT nanoprobes in combination with PT-OCT offer an exciting opportunity for stem cell tracking in vitro for assessing seeding scaffolds and in vivo for determining biodistribution.

  12. 3D scanning and 3D printing as innovative technologies for fabricating personalized topical drug delivery systems.

    Goyanes, Alvaro; Det-Amornrat, Usanee; Wang, Jie; Basit, Abdul W; Gaisford, Simon

    2016-07-28

    Acne is a multifactorial inflammatory skin disease with high prevalence. In this work, the potential of 3D printing to produce flexible personalised-shape anti-acne drug (salicylic acid) loaded devices was demonstrated by two different 3D printing (3DP) technologies: Fused Deposition Modelling (FDM) and stereolithography (SLA). 3D scanning technology was used to obtain a 3D model of a nose adapted to the morphology of an individual. In FDM 3DP, commercially produced Flex EcoPLA™ (FPLA) and polycaprolactone (PCL) filaments were loaded with salicylic acid by hot melt extrusion (HME) (theoretical drug loading - 2% w/w) and used as feedstock material for 3D printing. Drug loading in the FPLA-salicylic acid and PCL-salicylic acid 3D printed patches was 0.4% w/w and 1.2% w/w respectively, indicating significant thermal degradation of drug during HME and 3D printing. Diffusion testing in Franz cells using a synthetic membrane revealed that the drug loaded printed samples released printed as a nose-shape mask by FDM 3DP, but the PCL-salicylic acid filament was not. In the SLA printing process, the drug was dissolved in different mixtures of poly(ethylene glycol) diacrylate (PEGDA) and poly(ethylene glycol) (PEG) that were solidified by the action of a laser beam. SLA printing led to 3D printed devices (nose-shape) with higher resolution and higher drug loading (1.9% w/w) than FDM, with no drug degradation. The results of drug diffusion tests revealed that drug diffusion was faster than with the FDM devices, 229 and 291μg/cm(2) within 3h for the two formulations evaluated. In this study, SLA printing was the more appropriate 3D printing technology to manufacture anti-acne devices with salicylic acid. The combination of 3D scanning and 3D printing has the potential to offer solutions to produce personalised drug loaded devices, adapted in shape and size to individual patients.

  13. Virtual Realization using 3D Password

    A.B.Gadicha

    2012-03-01

    Full Text Available Current authentication systems suffer from many weaknesses. Textual passwords are commonly used; however, users do not follow their requirements. Users tend to choose meaningful words from dictionaries, which make textual passwords easy to break and vulnerable to dictionary or brute force attacks. Many available graphical passwords have a password space that is less than or equal to the textual password space. Smart cards or tokens can be stolen. Many biometric authentications have been proposed; however, users tend to resist using biometrics because of their intrusiveness and the effect on their privacy. Moreover, biometrics cannot be revoked. In this paper, we present and evaluate our contribution, i.e., the 3D password. The 3D password is a multifactor authentication scheme. To be authenticated, we present a 3D virtual environment where the user navigates and interacts with various objects. The sequence of actions and interactions toward the objects inside the 3D environment constructs the user’s 3D password. The 3D password can combine most existing authentication schemes such as textual passwords, graphical passwords, and various types of biometrics into a 3D virtual environment. The design of the 3D virtual environment and the type of objects selected determine the 3D password key space.

  14. Thermal Environment evaluation in Commercial kitchens

    Simone, Angela; Olesen, Bjarne W.

    2012-01-01

    and arrangement of the kitchen zones, appliances, etc., complicate further an evaluation of the indoor thermal environment in kitchens. In general, comfort criteria are expressed in international standards such as ASHRAE 55 or ISO EN7730. But are these standardised methods applicable for such environments...... as commercial kitchens? There is therefore a need to study the indoor environment in commercial kitchens and to establish standardized methods and procedures for setting criteria that have to be met for the design and operation of kitchens. The present paper introduces a data collection protocol based...... on physical and subjective parameters. Measurements showed weak and strong points of the procedure in order to evaluate the thermal comfort environment in commercial kitchens and its acceptability....

  15. A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT). Part II: On 3D model accuracy

    Liang Xin, E-mail: Xin.Liang@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); College of Stomatology, Dalian Medical University (China); Lambrichts, Ivo, E-mail: Ivo.Lambrichts@uhasselt.b [Department of Basic Medical Sciences, Histology and Electron Microscopy, Faculty of Medicine, University of Hasselt, Diepenbeek (Belgium); Sun Yi, E-mail: Sunyihello@hotmail.co [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Denis, Kathleen, E-mail: kathleen.denis@groept.b [Department of Industrial Sciences and Techology-Engineering (IWT), XIOS Hogeschool Limburg, Hasselt (Belgium); Hassan, Bassam, E-mail: b.hassan@acta.n [Department of Oral Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam (Netherlands); Li Limin, E-mail: Limin.Li@uz.kuleuven.b [Department of Paediatric Dentistry and Special Dental Care, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Pauwels, Ruben, E-mail: Ruben.Pauwels@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Jacobs, Reinhilde, E-mail: Reinhilde.Jacobs@uz.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium)

    2010-08-15

    Aim: The study aim was to compare the geometric accuracy of three-dimensional (3D) surface model reconstructions between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system. Materials and methods: A dry human mandible was scanned with five CBCT systems (NewTom 3G, Accuitomo 3D, i-CAT, Galileos, Scanora 3D) and one MSCT scanner (Somatom Sensation 16). A 3D surface bone model was created from the six systems. The reference (gold standard) 3D model was obtained with a high resolution laser surface scanner. The 3D models from the five systems were compared with the gold standard using a point-based rigid registration algorithm. Results: The mean deviation from the gold standard for MSCT was 0.137 mm and for CBCT were 0.282, 0.225, 0.165, 0.386 and 0.206 mm for the i-CAT, Accuitomo, NewTom, Scanora and Galileos, respectively. Conclusion: The results show that the accuracy of CBCT 3D surface model reconstructions is somewhat lower but acceptable comparing to MSCT from the gold standard.

  16. Evaluation of potential human health effects associated with the agricultural uses of 1,3-D: Spatial and temporal stochastic risk analysis.

    Driver, Jeffrey H; Price, Paul S; Van Wesenbeeck, Ian; Ross, John H; Gehen, Sean; Holden, Larry R; Landenberger, Bryce; Hastings, Kerry; Yan, Zhongyu June; Rasoulpour, Reza

    2016-11-15

    Dow AgroSciences (DAS) markets and sells 1,3-Dichloropropene (1,3-D), the active ingredient in Telone®, which is used as a pre-plant soil fumigant nematicide in economically important crops in California. 1,3-D has been regulated as a "probable human carcinogen" and the California Department of Pesticide Regulation limits use of 1,3-D based on human health risk assessments for bystanders. This paper presents a risk characterization for bystanders based on advances in the assessment of both exposure and hazard. The revised bystander risk assessment incorporates significant advances: 1) new data on residency duration and mobility in communities where 1,3-D is in high demand; 2) new information on spatial and temporal concentrations of 1,3-D in air based on multi-year modeling using a validated model; and 3) a new stochastic spatial and temporal model of long-term exposures. Predicted distributions of long-term, chronic exposures indicate that current, and anticipated uses of 1,3-D would result in lifetime average daily doses lower than 0.002mg/kg/d, a dose associated with theoretical lifetime excess cancer risk of 95% of the local population based on a non-threshold risk assessment approach. Additionally, examination of 1,3-D toxicity studies including new chronic toxicity data and mechanism of action supports the use of a non-linear, threshold based risk assessment approach. The estimated maximum annual average daily dose of 1000-fold, a clear indication of acceptable risk for human health. In summary, the best available science supports 1,3-D's threshold nature of hazard and the revised exposure assessment supports that current agricultural uses of 1,3-D are associated with reasonable certainty of no harm, i.e., estimated long-term exposures pose insignificant health risks to bystanders even when the non-threshold approach is assumed.

  17. 3D J-Integral Capability in Grizzly

    Benjamin Spencer; Marie Backman; Pritam Chakraborty; William Hoffman

    2014-09-01

    This report summarizes work done to develop a capability to evaluate fracture contour J-Integrals in 3D in the Grizzly code. In the current fiscal year, a previously-developed 2D implementation of a J-Integral evaluation capability has been extended to work in 3D, and to include terms due both to mechanically-induced strains and due to gradients in thermal strains. This capability has been verified against a benchmark solution on a model of a curved crack front in 3D. The thermal term in this integral has been verified against a benchmark problem with a thermal gradient. These developments are part of a larger effort to develop Grizzly as a tool that can be used to predict the evolution of aging processes in nuclear power plant systems, structures, and components, and assess their capacity after being subjected to those aging processes. The capabilities described here have been developed to enable evaluations of Mode- stress intensity factors on axis-aligned flaws in reactor pressure vessels. These can be compared with the fracture toughness of the material to determine whether a pre-existing flaw would begin to propagate during a pos- tulated pressurized thermal shock accident. This report includes a demonstration calculation to show how Grizzly is used to perform a deterministic assessment of such a flaw propagation in a degraded reactor pressure vessel under pressurized thermal shock conditions. The stress intensity is calculated from J, and the toughness is computed using the fracture master curve and the degraded ductile to brittle transition temperature.

  18. 3-D thermal analysis using finite difference technique with finite element model for improved design of components of rocket engine turbomachines for Space Shuttle Main Engine SSME

    Sohn, Kiho D.; Ip, Shek-Se P.

    1988-01-01

    Three-dimensional finite element models were generated and transferred into three-dimensional finite difference models to perform transient thermal analyses for the SSME high pressure fuel turbopump's first stage nozzles and rotor blades. STANCOOL was chosen to calculate the heat transfer characteristics (HTCs) around the airfoils, and endwall effects were included at the intersections of the airfoils and platforms for the steady-state boundary conditions. Free and forced convection due to rotation effects were also considered in hollow cores. Transient HTCs were calculated by taking ratios of the steady-state values based on the flow rates and fluid properties calculated at each time slice. Results are presented for both transient plots and three-dimensional color contour isotherm plots; they were also converted into universal files to be used for FEM stress analyses.

  19. Design and Evaluation of a Fiber-Optic Grip Force Sensor with Compliant 3D-Printable Structure for (fMRI Applications

    Tobias L. Bützer

    2016-01-01

    Full Text Available Grip force sensors compatible with magnetic resonance imaging (MRI are used in human motor control and decision-making research, providing objective and sensitive behavioral outcome measures. Commercial sensors are expensive, cover limited force ranges, rely on pneumatic force transmission that cannot detect fast force changes, or are electrically active, which increases the risk of electromagnetic interference. We present the design and evaluation of a low-cost, 3D-printed, inherently MRI-compatible grip force sensor based on a commercial intensity-based fiber-optic sensor. A compliant monobloc structure with flexible hinges transduces grip force to a linear displacement captured by the fiber-optic sensor. The structure can easily be adapted for different force ranges by changing the hinge thickness. A prototype designed for forces up to 800 N was manufactured and showed a highly linear behavior (nonlinearity of 2.37% and an accuracy of 1.57% in a range between zero and 500 N. It can be printed and assembled within one day and for less than $300. Accurate performance was confirmed, both inside and outside a 3 T MRI scanner within a pilot study. Given its simple design allowing for customization of sensing properties and ergonomics for different applications and requirements, the proposed grip force handle offers researchers a valuable scientific tool.

  20. The discovery of a novel and selective inhibitor of PTP1B over TCPTP: 3D QSAR pharmacophore modeling, virtual screening, synthesis, and biological evaluation.

    Ma, Ying; Jin, Yuan-Yuan; Wang, Ye-Liu; Wang, Run-Ling; Lu, Xin-Hua; Kong, De-Xin; Xu, Wei-Ren

    2014-06-01

    Given the special role of insulin and leptin signaling in various biological responses, protein-tyrosine phosphatase-1B (PTP1B) was regarded as a novel therapeutic target for treating type 2 diabetes and obesity. However, owing to the highly conserved (sequence identity of about 74%) in active pocket, targeting PTP1B for drug discovery is a great challenge. In this study, we employed the software package Discovery Studio to develop 3D QSAR pharmacophore models for PTP1B and TCPTP inhibitors. It was further validated by three methods (cost analysis, test set prediction, and Fisher's test) to show that the models can be used to predict the biological activities of compounds without costly and time-consuming synthesis. The criteria for virtual screening were also validated by testing the selective PTP1B inhibitors. Virtual screening experiments and subsequent in vitro evaluation of promising hits revealed a novel and selective inhibitor of PTP1B over TCPTP. After that, a most likely binding mode was proposed. Thus, the findings reported here may provide a new strategy in discovering selective PTP1B inhibitors.

  1. 3D nanocomposite chitosan/bioactive glass scaffolds obtained using two different routes: an evaluation of the porous structure and mechanical properties

    Elke M. F. Lemos

    2016-05-01

    Full Text Available Porous synthetic substrates are developed through tissue engineering technologies to grow new tissue, restoring the function of tissue or an organ. For bone regeneration, these scaffolds must support the dynamic load exerted on this tissue, achieved primarily by increasing their compression strength, as established in the literature. The aim of this paper was to incorporate an inorganic composite bioactive glass (60%SiO2 - 36%CaO - 4%P2O5 as a reinforcing agent in mechanical 3D scaffolds that must remain porous. Two strategies were adopted: a co-precipitation method to obtain a nanoparticulate dispersion of bioactive glass (BGNP and a sol-gel method to combine a bioactive glass solution (BG with a previously prepared chitosan polymer solution. Moreover, a lyophilization process was also used, generating highly porous scaffolds. Various aspects of the scaffold were evaluated, including the morphology, orientation and size of the pores, and mechanical strength, as obtained using the two synthetic methods. The data for compressive strength revealed increased strength after the incorporation of bioactive glass, which was more pronounced when utilizing the nanoscale bioactive glass.

  2. Evaluation of local electric fields generated by transcranial direct current stimulation with an extracephalic reference electrode based on realistic 3D body modeling

    Im, Chang-Hwan; Park, Ji-Hye; Shim, Miseon; Chang, Won Hyuk; Kim, Yun-Hee

    2012-04-01

    In this study, local electric field distributions generated by transcranial direct current stimulation (tDCS) with an extracephalic reference electrode were evaluated to address extracephalic tDCS safety issues. To this aim, we generated a numerical model of an adult male human upper body and applied the 3D finite element method to electric current conduction analysis. In our simulations, the active electrode was placed over the left primary motor cortex (M1) and the reference electrode was placed at six different locations: over the right temporal lobe, on the right supraorbital region, on the right deltoid, on the left deltoid, under the chin, and on the right buccinator muscle. The maximum current density and electric field intensity values in the brainstem generated by the extracephalic reference electrodes were comparable to, or even less than, those generated by the cephalic reference electrodes. These results suggest that extracephalic reference electrodes do not lead to unwanted modulation of the brainstem cardio-respiratory and autonomic centers, as indicated by recent experimental studies. The volume energy density was concentrated at the neck area by the use of deltoid reference electrodes, but was still smaller than that around the active electrode locations. In addition, the distributions of elicited cortical electric fields demonstrated that the use of extracephalic reference electrodes might allow for the robust prediction of cortical modulations with little dependence on the reference electrode locations.

  3. Wireless 3D Chocolate Printer

    FROILAN G. DESTREZA

    2014-02-01

    Full Text Available This study is for the BSHRM Students of Batangas State University (BatStateU ARASOF for the researchers believe that the Wireless 3D Chocolate Printer would be helpful in their degree program especially on making creative, artistic, personalized and decorative chocolate designs. The researchers used the Prototyping model as procedural method for the successful development and implementation of the hardware and software. This method has five phases which are the following: quick plan, quick design, prototype construction, delivery and feedback and communication. This study was evaluated by the BSHRM Students and the assessment of the respondents regarding the software and hardware application are all excellent in terms of Accuracy, Effecitveness, Efficiency, Maintainability, Reliability and User-friendliness. Also, the overall level of acceptability of the design project as evaluated by the respondents is excellent. With regard to the observation about the best raw material to use in 3D printing, the chocolate is good to use as the printed material is slightly distorted,durable and very easy to prepare; the icing is also good to use as the printed material is not distorted and is very durable but consumes time to prepare; the flour is not good as the printed material is distorted, not durable but it is easy to prepare. The computation of the economic viability level of 3d printer with reference to ROI is 37.14%. The recommendation of the researchers in the design project are as follows: adding a cooling system so that the raw material will be more durable, development of a more simplified version and improving the extrusion process wherein the user do not need to stop the printing process just to replace the empty syringe with a new one.

  4. Evaluation of brain perfusion in specific Brodmann areas in Frontotemporal dementia and Alzheimer disease using automated 3-D voxel based analysis

    Valotassiou, V; Tsougos, I; Tzavara, C; Georgoulias, P [Nuclear Medicine Dpt, University Hospital of Larissa, Larissa (Greece); Papatriantafyllou, J; Karageorgiou, C [Neurology Dpt, General Hospital ' G. Gennimatas' , Athens (Greece); Sifakis, N; Zerva, C [Nuclear Medicine Dpt, ' Alexandra' University Hospital, Athens (Greece)], E-mail: vanvalot@yahoo.gr

    2009-05-15

    Introduction. Brain perfusion studies with single-photon emission computed tomography (SPECT) have been applied in demented patients to provide better discrimination between frontotemporal dementia (FTD) and Alzheimer's disease (AD). Aim. To assess the perfusion of specific Brodmann (Br) areas of the brain cortex in FTD and AD patients, using NeuroGam processing program to provide 3D voxel-by-voxel cerebral SPECT analysis. Material and methods. We studied 34 consecutive patients. We used the established criteria for the diagnosis of dementia and the specific established criteria for the diagnosis of FTD and AD. All the patients had a neuropsychological evaluation with a battery of tests including the mini-mental state examination (MMSE).Twenty-six patients (16 males, 10 females, mean age 68.76{+-}6.51 years, education 11.81{+-}4.25 years, MMSE 16.69{+-}9.89) received the diagnosis of FTD and 8 patients (all females, mean age 71.25{+-}10.48 years, education 10{+-}4.6 years, MMSE 12.5{+-}3.89) the diagnosis of AD. All the patients underwent a brain SPECT. We applied the NeuroGam Software for the evaluation of brain perfusion in specific Br areas in the left (L) and right (R) hemispheres. Results. Statistically significant hypoperfusion in FTD compared to AD patients, was found in the following Br areas: 11L (p<0.0001), 11R, 20L, 20R, 32L, 38L, 38R, 44L (p<0.001), 32R, 36L, 36R, 45L, 45R, 47R (p<0.01), 9L, 21L, 39R, 44R, 46R, 47L (p<0.05). On the contrary, AD patients presented significant (p<0.05) hypoperfusion in 7R and 39R Br areas. Conclusion. NeuroGam processing program of brain perfusion SPECT could result in enhanced accuracy for the differential diagnosis between AD and FTD patients.

  5. 3D printing for dummies

    Hausman, Kalani Kirk

    2014-01-01

    Get started printing out 3D objects quickly and inexpensively! 3D printing is no longer just a figment of your imagination. This remarkable technology is coming to the masses with the growing availability of 3D printers. 3D printers create 3-dimensional layered models and they allow users to create prototypes that use multiple materials and colors.  This friendly-but-straightforward guide examines each type of 3D printing technology available today and gives artists, entrepreneurs, engineers, and hobbyists insight into the amazing things 3D printing has to offer. You'll discover methods for

  6. Comparação entre a ecocardiografia 2D e 3D na avaliação do remodelamento reverso após a TRC Comparación entre la ecocardiografía 2D y 3D en la evaluación del remodelado reverso después de la TRC Comparison between 2D and 3D echocardiography in the evaluation of reverse remodeling after CRT

    Viviane Tiemi Hotta

    2011-08-01

    izquierda (FEVI con excelente correlación de resultados cuando es comparado a la resonancia nuclear magnética (RNM. OBJETIVO: Comparar la evaluación de los volúmenes ventriculares (VDVI, VSVI, FEVI y masa del VI antes y después de la TRC por la ecocardiografía bi (Eco 2D y tridimensional (Eco 3D. MÉTODOS: Fueron evaluados 24 pacientes con insuficiencia cardíaca (IC, clase funcional (CF III o IV (NYHA, ritmo sinusal QRS > 120 ms, en vigencia de terapéutica optimizada para IC sometidos a TRC. Fueron realizados electrocardiograma (ECG, evaluación clínica, Eco 2D y 3D antes, tres y seis meses después de la TRC. La comparación entre las técnicas fue realizada utilizando la correlación de Pearson (r. RESULTADOS: En el momento basal, la correlación entre los métodos fue de 0,96 para evaluación del VDVI, 0,95 para evaluación del VSVI, 0,87 para FEVI, y 0,72 para masa del VI. Después de tres meses de la TRC, la correlación entre los métodos para análisis del VDVI fue de 0,96, 0,95 para VSVI, 0,95 para FEVI, y 0,77 para masa del VI. Después de seis meses de la TRC, la correlación entre el Eco 2D y 3D para análisis del VDVI fue de 0,98, 0,91 para VSVI, 0,96 para FEVI, y 0,85 para masa del VI. CONCLUSIÓN: En este estudio fue observada reducción de los VDVI,VSVI, además de mejora de la FEVI después de la TRC. Hubo excelente correlación entre el Eco 2D y el 3D para evaluación de los volúmenes ventriculares y FEVI, y buena correlación entre los métodos para evaluación de la masa ventricular izquierda antes y después de la TRC.BACKGROUND: Echocardiography is a useful method for screening and assessing response to cardiac resynchronization therapy (CRT. 3D echocardiography has already established its role in the evaluation of ventricular volumes and ejection fraction (LVEF with excellent correlation of results when compared with MRI. OBJECTIVE: To compare the evaluation of ventricular volumes (LVDV, LVSV, LVEF, and LV mass before and after CRT by 2D

  7. Evaluation of the scale dependent dynamic SGS model in the open source code caffa3d.MBRi in wall-bounded flows

    Draper, Martin; Usera, Gabriel

    2015-04-01

    The Scale Dependent Dynamic Model (SDDM) has been widely validated in large-eddy simulations using pseudo-spectral codes [1][2][3]. The scale dependency, particularly the potential law, has been proved also in a priori studies [4][5]. To the authors' knowledge there have been only few attempts to use the SDDM in finite difference (FD) and finite volume (FV) codes [6][7], finding some improvements with the dynamic procedures (scale independent or scale dependent approach), but not showing the behavior of the scale-dependence parameter when using the SDDM. The aim of the present paper is to evaluate the SDDM in the open source code caffa3d.MBRi, an updated version of the code presented in [8]. caffa3d.MBRi is a FV code, second-order accurate, parallelized with MPI, in which the domain is divided in unstructured blocks of structured grids. To accomplish this, 2 cases are considered: flow between flat plates and flow over a rough surface with the presence of a model wind turbine, taking for this case the experimental data presented in [9]. In both cases the standard Smagorinsky Model (SM), the Scale Independent Dynamic Model (SIDM) and the SDDM are tested. As presented in [6][7] slight improvements are obtained with the SDDM. Nevertheless, the behavior of the scale-dependence parameter supports the generalization of the dynamic procedure proposed in the SDDM, particularly taking into account that no explicit filter is used (the implicit filter is unknown). [1] F. Porté-Agel, C. Meneveau, M.B. Parlange. "A scale-dependent dynamic model for large-eddy simulation: application to a neutral atmospheric boundary layer". Journal of Fluid Mechanics, 2000, 415, 261-284. [2] E. Bou-Zeid, C. Meneveau, M. Parlante. "A scale-dependent Lagrangian dynamic model for large eddy simulation of complex turbulent flows". Physics of Fluids, 2005, 17, 025105 (18p). [3] R. Stoll, F. Porté-Agel. "Dynamic subgrid-scale models for momentum and scalar fluxes in large-eddy simulations of

  8. Intraoral 3D scanner

    Kühmstedt, Peter; Bräuer-Burchardt, Christian; Munkelt, Christoph; Heinze, Matthias; Palme, Martin; Schmidt, Ingo; Hintersehr, Josef; Notni, Gunther

    2007-09-01

    Here a new set-up of a 3D-scanning system for CAD/CAM in dental industry is proposed. The system is designed for direct scanning of the dental preparations within the mouth. The measuring process is based on phase correlation technique in combination with fast fringe projection in a stereo arrangement. The novelty in the approach is characterized by the following features: A phase correlation between the phase values of the images of two cameras is used for the co-ordinate calculation. This works contrary to the usage of only phase values (phasogrammetry) or classical triangulation (phase values and camera image co-ordinate values) for the determination of the co-ordinates. The main advantage of the method is that the absolute value of the phase at each point does not directly determine the coordinate. Thus errors in the determination of the co-ordinates are prevented. Furthermore, using the epipolar geometry of the stereo-like arrangement the phase unwrapping problem of fringe analysis can be solved. The endoscope like measurement system contains one projection and two camera channels for illumination and observation of the object, respectively. The new system has a measurement field of nearly 25mm × 15mm. The user can measure two or three teeth at one time. So the system can by used for scanning of single tooth up to bridges preparations. In the paper the first realization of the intraoral scanner is described.

  9. Martian terrain - 3D

    1997-01-01

    This area of terrain near the Sagan Memorial Station was taken on Sol 3 by the Imager for Mars Pathfinder (IMP). 3D glasses are necessary to identify surface detail.The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.' It stands 1.8 meters above the Martian surface, and has a resolution of two millimeters at a range of two meters.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  10. Estimating the relationship between urban 3D morphology and land surface temperature using airborne LiDAR and Landsat-8 Thermal Infrared Sensor data

    Lee, J. H.

    2015-12-01

    Urban forests are known for mitigating the urban heat island effect and heat-related health issues by reducing air and surface temperature. Beyond the amount of the canopy area, however, little is known what kind of spatial patterns and structures of urban forests best contributes to reducing temperatures and mitigating the urban heat effects. Previous studies attempted to find the relationship between the land surface temperature and various indicators of vegetation abundance using remote sensed data but the majority of those studies relied on two dimensional area based metrics, such as tree canopy cover, impervious surface area, and Normalized Differential Vegetation Index, etc. This study investigates the relationship between the three-dimensional spatial structure of urban forests and urban surface temperature focusing on vertical variance. We use a Landsat-8 Thermal Infrared Sensor image (acquired on July 24, 2014) to estimate the land surface temperature of the City of Sacramento, CA. We extract the height and volume of urban features (both vegetation and non-vegetation) using airborne LiDAR (Light Detection and Ranging) and high spatial resolution aerial imagery. Using regression analysis, we apply empirical approach to find the relationship between the land surface temperature and different sets of variables, which describe spatial patterns and structures of various urban features including trees. Our analysis demonstrates that incorporating vertical variance parameters improve the accuracy of the model. The results of the study suggest urban tree planting is an effective and viable solution to mitigate urban heat by increasing the variance of urban surface as well as evaporative cooling effect.

  11. Evaluation of thermal overload in boiler operators.

    Braga, Camila Soares; Rodrigues, Valéria Antônia Justino; Campos, Julio César Costa; de Souza, Amaury Paulo; Minette, Luciano José; de Moraes, Angêlo Casali; Sensato, Guilherme Luciano

    2012-01-01

    The Brazilians educational institutions need a large energy demand for the operation of laundries, restaurants and accommodation of students. Much of that energy comes from steam generated in boilers with wood fuel. The laboral activity in boiler may present problems for the operator's health due to exposure to excessive heat, and its operation has a high degree of risk. This paper describes an analysis made the conditions of thermal environment in the operation of a B category boiler, located at a Higher Education Institution, located in the Zona da Mata Mineira The equipments used to collect data were Meter WBGT of the Heat Index; Meter of Wet Bulb Index and Globe Thermometer (WBGT); Politeste Instruments, an anemometer and an Infrared Thermometer. By the application of questionnaires, the second phase consisted of collecting data on environmental factors (temperature natural environment, globe temperature, relative humidity and air velocity). The study concluded that during the period evaluated, the activity had thermal overload.

  12. Quantitative evaluation of ultrasonic wave propagation in inhomogeneous anisotropic austenitic welds using 3D ray tracing method. Numerical and experimental validation

    Kolkoori, Sanjeevareddy

    2014-07-01

    Austenitic welds and dissimilar welds are extensively used in primary circuit pipes and pressure vessels in nuclear power plants, chemical industries and fossil fuelled power plants because of their high fracture toughness, resistance to corrosion and creep at elevated temperatures. However, cracks may initiate in these weld materials during fabrication process or stress operations in service. Thus, it is very important to evaluate the structural integrity of these materials using highly reliable non-destructive testing (NDT) methods. Ultrasonic non-destructive inspection of austenitic welds and dissimilar weld components is complicated because of anisotropic columnar grain structure leading to beam splitting and beam deflection. Simulation tools play an important role in developing advanced reliable ultrasonic testing (UT) techniques and optimizing experimental parameters for inspection of austenitic welds and dissimilar weld components. The main aim of the thesis is to develop a 3D ray tracing model for quantitative evaluation of ultrasonic wave propagation in an inhomogeneous anisotropic austenitic weld material. Inhomogenity in the anisotropic weld material is represented by discretizing into several homogeneous layers. According to ray tracing model, ultrasonic ray paths are traced during its energy propagation through various discretized layers of the material and at each interface the problem of reflection and transmission is solved. The influence of anisotropy on ultrasonic reflection and transmission behaviour in an anisotropic austenitic weld material are quantitatively analyzed in three dimensions. The ultrasonic beam directivity in columnar grained austenitic steel material is determined three dimensionally using Lamb's reciprocity theorem. The developed ray tracing model evaluates the transducer excited ultrasonic fields accurately by taking into account the directivity of the transducer, divergence of the ray bundle, density of rays and phase

  13. mTOR-inhibitor treatment of metastatic renal cell carcinoma: contribution of Choi and modified Choi criteria assessed in 2D or 3D to evaluate tumor response

    Lamuraglia, M. [Laboratoire d' Imagerie Biomedicale, Sorbonne Universites, UPMC Univ Paris 06, INSERM, CNRS, Paris (France); Raslan, S.; Penna, R.R.; Wagner, M. [Groupe Hospitalier Pitie-Salpetriere, APHP UPMC, Service de Radiologie Polyvalente et Oncologique, Paris Cedex 13 (France); Elaidi, R.; Oudard, S. [APHP, Oncology Unit, Georges-Pompidou Hospital, Paris (France); Escudier, B. [Gustave-Roussy Institute, Medical Oncology Department, Villejuif (France); Slimane, K. [Novartis Pharma, Rueil-Malmaison (France); Lucidarme, O. [Groupe Hospitalier Pitie-Salpetriere, APHP UPMC, Service de Radiologie Polyvalente et Oncologique, Paris Cedex 13 (France); Laboratoire d' Imagerie Biomedicale, Sorbonne Universites, UPMC Univ Paris 06, INSERM, CNRS, Paris (France)

    2016-01-15

    To determine whether 2D or 3D Choi and modified Choi (mChoi) criteria could assess the efficacy of everolimus against metastatic renal cell carcinoma (mRCC). RECIST-1.1, Choi, and mChoi criteria were applied retrospectively to analyse baseline and 2-month contrast-enhanced computed tomography (CECT) images in 48 patients with mRCC enrolled in the everolimus arm of the French randomized double-blind multicentre phase III trial comparing everolimus versus placebo (RECORD-1). The primary endpoint was centrally reviewed progression-free survival (PFS) calculated from the initial RECORD-1 analysis. Mean attenuation was determined for 2D target lesion regions of interest drawn on CECT sections whose largest diameters had been measured, and for the 3D whole target lesion. The median PFS was 5.5 months. The median PFS for everolimus responders defined using 3D mChoi criteria was significantly longer than for non-responders (7.6 versus 5.4 months, respectively), corresponding to a hazard ratio for progression of 0.45 (95 % CI: 0.22-0.92), with respective 1-year survival rates of 31 % and 9 %. No other 2D or 3D imaging criteria at 2 months identified patients who would benefit from everolimus. At 2 months, only 3D mChoi criteria were able to identify mRCC patients with a PFS benefit from everolimus. (orig.)

  14. 3D Printing an Octohedron

    Aboufadel, Edward F.

    2014-01-01

    The purpose of this short paper is to describe a project to manufacture a regular octohedron on a 3D printer. We assume that the reader is familiar with the basics of 3D printing. In the project, we use fundamental ideas to calculate the vertices and faces of an octohedron. Then, we utilize the OPENSCAD program to create a virtual 3D model and an STereoLithography (.stl) file that can be used by a 3D printer.

  15. 异步电动机定子铁心3D等效热路模型研究%Research of Asychronous Motor Stator Core 3 D Thermal Circuit Model

    田井呈; 邓自清; 王飞宇; 卓克琼; 赵朝会

    2016-01-01

    According to asynchronous motor stator core asymmetry flux density distribution and material heat conduction characteristic,drawed a eight heat resources 3D thermal circuit model for a 7. 5 kW forced air cooling squirrel-cage rotor asynchronous motor, and then use this model calculated stator core temperature distribution based on motor thermal circuit software motor-CAD. The result agreement well with finite element method. This model have a certain reference value for motor thermal analysis and study.%根据异步电动机定子铁心磁密分布不均匀的情况和铁心材料的导热特点,以一台7. 5 kW强迫风冷异步电动机为例,基于3D热路法绘制了定子铁心的8热源等效热路模型,并利用Motor-CAD电机热路计算软件计算了定子铁心的温度分布. 计算结果与采用有限元法相近,证明了该模型的合理性和可行性,对电机温度场的分析和研究具有一定的参考价值.

  16. Salient Local 3D Features for 3D Shape Retrieval

    Godil, Afzal

    2011-01-01

    In this paper we describe a new formulation for the 3D salient local features based on the voxel grid inspired by the Scale Invariant Feature Transform (SIFT). We use it to identify the salient keypoints (invariant points) on a 3D voxelized model and calculate invariant 3D local feature descriptors at these keypoints. We then use the bag of words approach on the 3D local features to represent the 3D models for shape retrieval. The advantages of the method are that it can be applied to rigid as well as to articulated and deformable 3D models. Finally, this approach is applied for 3D Shape Retrieval on the McGill articulated shape benchmark and then the retrieval results are presented and compared to other methods.

  17. THERMAL EVALUATION OF DIFFERENT DRIFT DIAMETER SIZES

    H.M. Wade

    1999-01-04

    The purpose of this calculation is to estimate the thermal response of a repository-emplaced waste package and its corresponding drift wall surface temperature with different drift diameters. The case examined is that of a 21 pressurized water reactor (PWR) uncanistered fuel (UCF) waste package loaded with design basis spent nuclear fuel assemblies. This calculation evaluates a 3.5 meter to 6.5 meter drift diameter range in increments of 1.0 meters. The time-dependent temperatures of interest, as determined by this calculation, are the spent nuclear fuel cladding temperature, the waste package surface temperature, and the drift wall surface temperature.

  18. Crystal Structure, Thermal Decomposition Behavior and the Standard Molar Enthalpy of Formation of a Novel 3D Hydrogen Bonded Supramolecular [Co(HnicO)2·(H2O)2

    ZENG,Ming-Hua; WU,Mei-Chun; ZHU,Li-Hong; LIANG,Hong; YANG Xu-Wu

    2007-01-01

    Hydrothermal synthesis and X-ray characterized 3D supramolecular networks were constructed by [Co(HnicO)2·(H2O)2] (HnicOH=2-hydroxynicotinic acid) (1) as building block via abundant dimeric homomeric (N-H…O) and unusually cyclic tetrameric heteromeric (O-H…O) hydrogen-bonds. It is noted that there exist unusually linear metal-water chains comprised of tetrameric units linked by vertexes sharing cobalt centers through hydrogen-bonding. TG-DTG curves illustrated that thermal decomposition was completed by two steps, one is the loss of two terminal water molecules in the range of 156-234 ℃, and the other is the pyrolysis of HnicO ligand in the range of 234-730 ℃. The standard molar enthalpy of formation of the complex was determined to be (-1845.43±2.77) kJ·mol-1 by a rotary-bomb combustion calorimeter.

  19. A new bioactive Schiff base ligands derived from propylazo-N-pyrimidin-2-yl-benzenesulfonamides Mn(II) and Cu(II) complexes: synthesis, thermal and spectroscopic characterization biological studies and 3D modeling structures.

    Tawfik, Abdelrazak M; El-Ghamry, Mosad A; Abu-El-Wafa, Samy M; Ahmed, Naglaa M

    2012-11-01

    New series of Schiff base ligand H(2)L and their Cu(II) and Mn(II) complexes derived from azosulfapyrimidine were synthesized and characterized by elemental and thermal studies conductance measurements IR, electronic and EPR spectra. 3D modeling of the ligand indicate that azo group does not participate in complex formation and surface potential on one of the ligand under study indicate that electron density around azomethine groups are much higher than the azo group therefore coordination takes place around azomethine groups. The variety in the geometrical structures depends on the nature of both the metal ions and the Schiff base ligands. The thermo kinetic parameters are calculated and discussed. The biological activities of the ligands and complexes have been screened in vitro against some bacteria and fungi to study their capacity to inhibit their growth and to study the toxicity of the compounds.

  20. Synthesis and Biological Evaluation of Well-Defined Poly(propylene fumarate) Oligomers and Their Use in 3D Printed Scaffolds.

    Luo, Yuanyuan; Dolder, Courtney K; Walker, Jason M; Mishra, Ruchi; Dean, David; Becker, Matthew L

    2016-02-08

    A ring opening polymerization method for synthesizing oligomeric poly(propylene fumarate) (PPF) provides a rapid, and scalable method of synthesizing PPF with well-defined molecular mass, molecular mass distribution (Đm), and viscosity properties suitable for 3D printing. These properties will also reduce the amount of solvent necessary to ensure sufficient flow of material during 3D printing. MALDI mass spectrometry precisely shows the end group fidelity, and size exclusion chromatography (SEC) demonstrates narrow mass distributions (3000 Da). The corresponding intrinsic viscosities range from 0.0288 ± 0.0009 dL/g to 0.0780 ± 0.0022 dL/g. The oligomers were printed into scaffolds via established photochemical methods and standardized ISO 10993-5 testing shows that the 3D printed materials are nontoxic to both L929 mouse fibroblasts and human mesenchymal stem cells.

  1. Monte Carlo evaluation of a CZT 3D spectrometer suitable for a Hard X- and soft-γ rays polarimetry balloon borne experiment

    Caroli, E.; De Cesare, G.; Curado da Silva, R. M.

    2015-01-01

    . The detector with 3D spatial resolution is based on a CZT spectrometer in a highly segmented configuration designed to operate simultaneously as a high performance scattering polarimeter. Herein, we report results of a Monte Carlo study devoted to optimize the configuration of the detector for polarimetry...... with particular focus on event selection filter able to increase the polarimetric performance. This preliminary analysis shows that a procedure to optimize the polarization response of a 3D spectrometers should first of all determine the best tradeoff between the statistical significance and the quality...

  2. Quantitative Comparison of 2D and 3D MRI Techniques for the Evaluation of Chondromalacia Patellae in 3.0T MR Imaging of the Knee

    Ali Özgen

    2016-09-01

    Full Text Available INTRODUCTION: Chondromalacia patellae is a very common disorder of patellar cartilage. Magnetic resonance imaging (MRI is a powerful non-invasive tool to investigate patellar cartilage lesions. Although many MRI sequences have been used in MR imaging of the patellar cartilage and the optimal pulse sequence is controversial, fat-saturated proton density images have been considered very valuable to evaluate patellar cartilage. The purpose of this study is to quantitatively compare the diagnostic performance of various widely used 2D and 3D MRI techniques for the evaluation of chondromalacia patellae in 3.0T MR imaging of the knee using T2 mapping images as the reference standard. METHODS: Sevety-five knee MRI exams of 69 adult consecutive were included in the study. Fat-saturated T2-weighted (FST2, fat-saturated proton density (FSPD, water-only T2-weighted DIXON (T2mD, T2-weighted 3 dimensional steady state (3DT2FFE, merged multi-echo steady state (3DmFFE, and water selective T1-weighted fat-supressed (WATSc images were acquired. Quantitative comparison of grade 1 and grade 5 lesions were made using contrast-to-noise (CNR ratios. Grade 2-4 lesions were scored qualitatively and scorings of the lesions were compared statistically. Analysis of variance and Tukey’s tests were used to compare CNR data. Two sample z-test was used to compare the ratio of MR exams positive for grade 1 lesions noted on T2-mapping and other conventional sequences. Paired samples t-test was used to compare two different pulse sequences. RESULTS: In detecting grade 1 lesions, FSPD, FST2 and T2mD images were superior in comparison to other sequences. FSPD and FST2 images were statistically superior in detecting grade 2-4 lesions. Although all grade 5 lesions were noted in every single sequence, FST2 images have the highest mean CNR followed by 3DT2FFE images. DISCUSSION AND CONCLUSION: FST2 sequence is equal or superior in detecting every grade of patellar chondromalacia in

  3. Evaluation and comparison of 3D-QSAR CoMSIA models for CDK1, CDK5, and GSK-3 inhibition by paullones

    Kunick, Conrad; Lauenroth, Kathrin; Wieking, Karen;

    2004-01-01

    With a view to the rational design of selective GSK-3beta inhibitors, 3D-QSAR CoMSIA models were developed for the inhibition of the three serine/threonine kinases CDK1/cyclin B, CDK5/p25, and GSK-3beta by compounds from the paullone inhibitor family. The models are based on the kinase inhibition...

  4. A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT). Part II: On 3D model accuracy

    Liang, X.; Lambrichts, I.; Sun, Y.; Denis, K.; Hassan, B.; Li, L.; Pauwels, R.; Jacobs, R.

    2010-01-01

    Aim: The study aim was to compare the geometric accuracy of three-dimensional (3D) surface model reconstructions between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system. Materials and methods: A dry human mandible was scanned with five CBCT systems (NewTom 3G,

  5. Is 3D technique superior to 2D in Down syndrome screening? Evaluation of six second and third trimester fetal profile markers

    Vos, F. I.; Bakker, M.; de Jong-Pleij, E. A. P.; Ribbert, L. S. M.; Tromp, E.; Bilardo, C. M.

    2015-01-01

    ObjectiveThe objective of this article is to investigate whether in the clinical setting of second trimester ultrasound (US) investigations, 3D multiplanar correction prior to the measurement of Down syndrome (DS) facial markers (nasal bone length, prenasal thickness, fetal profile line, maxilla-nas

  6. Radiometric and geometric evaluation of GeoEye-1, WorldView-2 and Pléiades-1A stereo images for 3D information extraction

    Poli, D.; Remondino, F.; Angiuli, E.; Agugiaro, G.

    2015-02-01

    Today the use of spaceborne Very High Resolution (VHR) optical sensors for automatic 3D information extraction is increasing in the scientific and civil communities. The 3D Optical Metrology (3DOM) unit of the Bruno Kessler Foundation (FBK) in Trento (Italy) has collected VHR satellite imagery, as well as aerial and terrestrial data over Trento for creating a complete testfield for investigations on image radiometry, geometric accuracy, automatic digital surface model (DSM) generation, 2D/3D feature extraction, city modelling and data fusion. This paper addresses the radiometric and the geometric aspects of the VHR spaceborne imagery included in the Trento testfield and their potential for 3D information extraction. The dataset consist of two stereo-pairs acquired by WorldView-2 and by GeoEye-1 in panchromatic and multispectral mode, and a triplet from Pléiades-1A. For reference and validation, a DSM from airborne LiDAR acquisition is used. The paper gives details on the project, dataset characteristics and achieved results.

  7. Combination of 2D/3D Ligand-Based Similarity Search in Rapid Virtual Screening from Multimillion Compound Repositories. Selection and Biological Evaluation of Potential PDE4 and PDE5 Inhibitors

    Krisztina Dobi

    2014-05-01

    Full Text Available Rapid in silico selection of target focused libraries from commercial repositories is an attractive and cost effective approach. If structures of active compounds are available rapid 2D similarity search can be performed on multimillion compound databases but the generated library requires further focusing by various 2D/3D chemoinformatics tools. We report here a combination of the 2D approach with a ligand-based 3D method (Screen3D which applies flexible matching to align reference and target compounds in a dynamic manner and thus to assess their structural and conformational similarity. In the first case study we compared the 2D and 3D similarity scores on an existing dataset derived from the biological evaluation of a PDE5 focused library. Based on the obtained similarity metrices a fusion score was proposed. The fusion score was applied to refine the 2D similarity search in a second case study where we aimed at selecting and evaluating a PDE4B focused library. The application of this fused 2D/3D similarity measure led to an increase of the hit rate from 8.5% (1st round, 47% inhibition at 10 µM to 28.5% (2nd round at 50% inhibition at 10 µM and the best two hits had 53 nM inhibitory activities.

  8. FI3D : Direct-Touch Interaction for the Exploration of 3D Scientific Visualization Spaces

    Yu, Lingyun; Svetachov, Pjotr; Isenberg, Petra; Everts, Maarten H.; Isenberg, Tobias

    2010-01-01

    We present the design and evaluation of FI3D, a direct-touch data exploration technique for 3D visualization spaces. The exploration of three-dimensional data is core to many tasks and domains involving scientific visualizations. Thus, effective data navigation techniques are essential to enable com

  9. 3D Biomimetic Platform

    Scott Carnell, Lisa A. (Inventor)

    2017-01-01

    An apparatus and method that utilizes a radiation source and a simulated microgravity to provide combined stressors. The response of cells/bacteria/viruses and/or other living matter to the combined stressors can be evaluated to predict the effects of extended space missions. The apparatus and method can also be utilized to study diseases and to develop new treatments and vaccinations.

  10. 3D imaging in forensic odontology.

    Evans, Sam; Jones, Carl; Plassmann, Peter

    2010-06-16

    This paper describes the investigation of a new 3D capture method for acquiring and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded into a 2D space. Although strict guidelines (BAFO) exist, these are time-consuming to follow and, due to their complexity, may produce errors. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors. Proposed Solution: a series of experiments are described in this paper to demonstrate that the potential of a 3D system might produce suitable results. The experiments tested precision and accuracy of the traditional 2D and 3D methods. A 3D image capture device minimises the amount of angular distortion, therefore such a system has the potential to create more robust forensic evidence for use in courts. A first set of experiments tested and demonstrated which method of forensic analysis creates the least amount of intra-operator error. A second set tested and demonstrated which method of image capture creates the least amount of inter-operator error and visual distortion. In a third set the effects of angular distortion on 2D and 3D methods of image capture were evaluated.

  11. 40 CFR 91.427 - Catalyst thermal stress resistance evaluation.

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Catalyst thermal stress resistance... Procedures § 91.427 Catalyst thermal stress resistance evaluation. (a)(1) The purpose of the evaluation procedure specified in this section is to determine the effect of thermal stress on catalyst...

  12. 2D/3D Program work summary report

    NONE

    1995-09-01

    The 2D/3D Program was carried out by Germany, Japan and the United States to investigate the thermal-hydraulics of a PWR large-break LOCA. A contributory approach was utilized in which each country contributed significant effort to the program and all three countries shared the research results. Germany constructed and operated the Upper Plenum Test Facility (UPTF), and Japan constructed and operated the Cylindrical Core Test Facility (CCTF) and the Slab Core Test Facility (SCTF). The US contribution consisted of provision of advanced instrumentation to each of the three test facilities, and assessment of the TRAC computer code against the test results. Evaluations of the test results were carried out in all three countries. This report summarizes the 2D/3D Program in terms of the contributing efforts of the participants, and was prepared in a coordination among three countries. US and Germany have published the report as NUREG/IA-0126 and GRS-100, respectively. (author).

  13. Solar Particle Acceleration at Reconnecting 3D Null Points

    Stanier, Adam J; Dalla, Silvia

    2012-01-01

    Context: The strong electric fields associated with magnetic reconnection in solar flares are a plausible mechanism to accelerate populations of high energy, non-thermal particles. One such reconnection scenario occurs at a 3D magnetic null point, where global plasma flows give rise to strong currents in the spine axis or fan plane. Aims: To understand the mechanism of charged particle energy gain in both the external drift region and the diffusion region associated with 3D magnetic reconnection. In doing so we evaluate the efficiency of resistive spine and fan models for particle acceleration, and find possible observables for each. Method: We use a full orbit test particle approach to study proton trajectories within electromagnetic fields that are exact solutions to the steady and incompressible magnetohydrodynamic equations. We study single particle trajectories and find energy spectra from many particle simulations. The scaling properties of the accelerated particles with respect to field and plasma para...

  14. Quantitative evaluation of 3D mouse behaviors and motor function in the open-field after spinal cord injury using markerless motion tracking.

    Alison L Sheets

    Full Text Available Thousands of scientists strive to identify cellular mechanisms that could lead to breakthroughs in developing ameliorative treatments for debilitating neural and muscular conditions such as spinal cord injury (SCI. Most studies use rodent models to test hypotheses, and these are all limited by the methods available to evaluate animal motor function. This study's goal was to develop a behavioral and locomotor assessment system in a murine model of SCI that enables quantitative kinematic measurements to be made automatically in the open-field by applying markerless motion tracking approaches. Three-dimensional movements of eight naïve, five mild, five moderate, and four severe SCI mice were recorded using 10 cameras (100 Hz. Background subtraction was used in each video frame to identify the animal's silhouette, and the 3D shape at each time was reconstructed using shape-from-silhouette. The reconstructed volume was divided into front and back halves using k-means clustering. The animal's front Center of Volume (CoV height and whole-body CoV speed were calculated and used to automatically classify animal behaviors including directed locomotion, exploratory locomotion, meandering, standing, and rearing. More detailed analyses of CoV height, speed, and lateral deviation during directed locomotion revealed behavioral differences and functional impairments in animals with mild, moderate, and severe SCI when compared with naïve animals. Naïve animals displayed the widest variety of behaviors including rearing and crossing the center of the open-field, the fastest speeds, and tallest rear CoV heights. SCI reduced the range of behaviors, and decreased speed (r = .70 p<.005 and rear CoV height (r = .65 p<.01 were significantly correlated with greater lesion size. This markerless tracking approach is a first step toward fundamentally changing how rodent movement studies are conducted. By providing scientists with sensitive, quantitative

  15. 3D analysis of thermal exchange in finned batteries. A comparison between round and elliptical tubes; Analisi tridimensionale dello scambio termico nelle batterie alettate. Confronto fra tubi tondi e tubi ellittici

    Valdiserri, P. [Bologna Univ., Bologna (Italy). Facolta' di Ingegneria, Dipartimento di Ingegneria Energetica, Nucleare e del Controllo Ambientale

    2001-05-01

    In this paper a numerical 3D analysis of the thermal exchange in air-cooled finned batteries has been carried out. Speed and temperature values in each hub of the numerical simulation domain have been reckoned both at different air flows and with different shapes of the tubes. The thermal power exchanged between tubes and air is obtained by the simulation of a numerical model of a finned battery with round section tubes and is compared to the values obtained for three batteries with elliptical section tubes. The comparison has been performed for different values of the air input speed. [Italian] In questo lavoro e' stata condotta un'analisi numerica tridimensionale dei fenomeni di scambio termico in batterie alettate raffreddate ad aria. I valori di velocita' e temperatura nei singoli nodi del dominio di simulazione numerica sono stati calcolati sia al variare della portata dell'aria sia della forma dei tubi. La potenza termica scambiata tra tubi ed aria, ottenuta dalle simulazioni in un modello numerico di batteria alettata composta da tubi di sezione circolare, e' stata confrontata con i valori ottenuti per tre batterie formate da tubi di sezione elittica. Il confronto e' stato eseguito per diversi valori della velocita' d'ingresso dell'aria.

  16. 3D VISUALIZATION FOR VIRTUAL MUSEUM DEVELOPMENT

    M. Skamantzari

    2016-06-01

    Full Text Available The interest in the development of virtual museums is nowadays rising rapidly. During the last decades there have been numerous efforts concerning the 3D digitization of cultural heritage and the development of virtual museums, digital libraries and serious games. The realistic result has always been the main concern and a real challenge when it comes to 3D modelling of monuments, artifacts and especially sculptures. This paper implements, investigates and evaluates the results of the photogrammetric methods and 3D surveys that were used for the development of a virtual museum. Moreover, the decisions, the actions, the methodology and the main elements that this kind of application should include and take into consideration are described and analysed. It is believed that the outcomes of this application will be useful to researchers who are planning to develop and further improve the attempts made on virtual museums and mass production of 3D models.

  17. Measuring Visual Closeness of 3-D Models

    Morales, Jose A.

    2012-09-01

    Measuring visual closeness of 3-D models is an important issue for different problems and there is still no standardized metric or algorithm to do it. The normal of a surface plays a vital role in the shading of a 3-D object. Motivated by this, we developed two applications to measure visualcloseness, introducing normal difference as a parameter in a weighted metric in Metro’s sampling approach to obtain the maximum and mean distance between 3-D models using 3-D and 6-D correspondence search structures. A visual closeness metric should provide accurate information on what the human observers would perceive as visually close objects. We performed a validation study with a group of people to evaluate the correlation of our metrics with subjective perception. The results were positive since the metrics predicted the subjective rankings more accurately than the Hausdorff distance.

  18. 3D Spectroscopy in Astronomy

    Mediavilla, Evencio; Arribas, Santiago; Roth, Martin; Cepa-Nogué, Jordi; Sánchez, Francisco

    2011-09-01

    Preface; Acknowledgements; 1. Introductory review and technical approaches Martin M. Roth; 2. Observational procedures and data reduction James E. H. Turner; 3. 3D Spectroscopy instrumentation M. A. Bershady; 4. Analysis of 3D data Pierre Ferruit; 5. Science motivation for IFS and galactic studies F. Eisenhauer; 6. Extragalactic studies and future IFS science Luis Colina; 7. Tutorials: how to handle 3D spectroscopy data Sebastian F. Sánchez, Begona García-Lorenzo and Arlette Pécontal-Rousset.

  19. Spherical 3D isotropic wavelets

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2012-04-01

    Context. Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. Aims: The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the SFB decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. Methods: We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. (2006). We also present a new fast discrete spherical Fourier-Bessel transform (DSFBT) based on both a discrete Bessel transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large box cosmological simulations and find we can successfully remove noise without much loss to the large scale structure. Results: We have described a new spherical 3D isotropic wavelet transform, ideally suited to analyse and denoise future 3D spherical cosmological surveys, which uses a novel DSFBT. We illustrate its potential use for denoising using a toy model. All the algorithms presented in this paper are available for download as a public code called MRS3D at http://jstarck.free.fr/mrs3d.html

  20. 3D IBFV : Hardware-Accelerated 3D Flow Visualization

    Telea, Alexandru; Wijk, Jarke J. van

    2003-01-01

    We present a hardware-accelerated method for visualizing 3D flow fields. The method is based on insertion, advection, and decay of dye. To this aim, we extend the texture-based IBFV technique for 2D flow visualization in two main directions. First, we decompose the 3D flow visualization problem in a

  1. 3D Elevation Program—Virtual USA in 3D

    Lukas, Vicki; Stoker, J.M.

    2016-04-14

    The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.  

  2. 2-Arylpyrazolo[4,3-d]pyrimidin-7-amino derivatives as new potent and selective human A3 adenosine receptor antagonists. Molecular modeling studies and pharmacological evaluation.

    Squarcialupi, Lucia; Colotta, Vittoria; Catarzi, Daniela; Varano, Flavia; Filacchioni, Guido; Varani, Katia; Corciulo, Carmen; Vincenzi, Fabrizio; Borea, Pier Andrea; Ghelardini, Carla; Di Cesare Mannelli, Lorenzo; Ciancetta, Antonella; Moro, Stefano

    2013-03-28

    On the basis of our previously reported 2-arylpyrazolo[4,3-d]pyrimidin-7-ones, a set of 2-arylpyrazolo[4,3-d]pyrimidin-7-amines were designed as new human (h) A3 adenosine receptor (AR) antagonists. Lipophilic groups with different steric bulk were introduced at the 5-position of the bicyclic scaffold (R5 = Me, Ph, CH2Ph), and different acyl and carbamoyl moieties (R7) were appended on the 7-amino group, as well as a para-methoxy group inserted on the 2-phenyl ring. The presence of acyl groups turned out to be of paramount importance for an efficient and selective binding at the hA3 AR. In fact, most of the 7-acylamino derivatives showed low nanomolar affinity (Ki = 2.5-45 nM) and high selectivity toward this receptor. A few selected pyrazolo[4,3-d]pyrimidin-7-amides were effective in counteracting oxaliplatin-induced apoptosis in rat astrocyte cell cultures, an in vitro model of neurotoxicity. Through an in silico receptor-driven approach the obtained binding data were rationalized and the molecular bases of the observed hA3 AR affinity and hA3 versus hA2A AR selectivity were explained.

  3. Interactive 3D multimedia content

    Cellary, Wojciech

    2012-01-01

    The book describes recent research results in the areas of modelling, creation, management and presentation of interactive 3D multimedia content. The book describes the current state of the art in the field and identifies the most important research and design issues. Consecutive chapters address these issues. These are: database modelling of 3D content, security in 3D environments, describing interactivity of content, searching content, visualization of search results, modelling mixed reality content, and efficient creation of interactive 3D content. Each chapter is illustrated with example a

  4. A 3-D Contextual Classifier

    Larsen, Rasmus

    1997-01-01

    . This includes the specification of a Gaussian distribution for the pixel values as well as a prior distribution for the configuration of class variables within the cross that is m ade of a pixel and its four nearest neighbours. We will extend this algorithm to 3-D, i.e. we will specify a simultaneous Gaussian...... distr ibution for a pixel and its 6 nearest 3-D neighbours, and generalise the class variable configuration distribution within the 3-D cross. The algorithm is tested on a synthetic 3-D multivariate dataset....

  5. 3D Bayesian contextual classifiers

    Larsen, Rasmus

    2000-01-01

    We extend a series of multivariate Bayesian 2-D contextual classifiers to 3-D by specifying a simultaneous Gaussian distribution for the feature vectors as well as a prior distribution of the class variables of a pixel and its 6 nearest 3-D neighbours.......We extend a series of multivariate Bayesian 2-D contextual classifiers to 3-D by specifying a simultaneous Gaussian distribution for the feature vectors as well as a prior distribution of the class variables of a pixel and its 6 nearest 3-D neighbours....

  6. 3-D printers for libraries

    Griffey, Jason

    2014-01-01

    As the maker movement continues to grow and 3-D printers become more affordable, an expanding group of hobbyists is keen to explore this new technology. In the time-honored tradition of introducing new technologies, many libraries are considering purchasing a 3-D printer. Jason Griffey, an early enthusiast of 3-D printing, has researched the marketplace and seen several systems first hand at the Consumer Electronics Show. In this report he introduces readers to the 3-D printing marketplace, covering such topics asHow fused deposition modeling (FDM) printing workBasic terminology such as build

  7. 3D for Graphic Designers

    Connell, Ellery

    2011-01-01

    Helping graphic designers expand their 2D skills into the 3D space The trend in graphic design is towards 3D, with the demand for motion graphics, animation, photorealism, and interactivity rapidly increasing. And with the meteoric rise of iPads, smartphones, and other interactive devices, the design landscape is changing faster than ever.2D digital artists who need a quick and efficient way to join this brave new world will want 3D for Graphic Designers. Readers get hands-on basic training in working in the 3D space, including product design, industrial design and visualization, modeling, ani

  8. 3D-PRINTING OF BUILD OBJECTS

    SAVYTSKYI M. V.

    2016-03-01

    Full Text Available Raising of problem. Today, in all spheres of our life we can constate the permanent search for new, modern methods and technologies that meet the principles of sustainable development. New approaches need to be, on the one hand more effective in terms of conservation of exhaustible resources of our planet, have minimal impact on the environment and on the other hand to ensure a higher quality of the final product. Construction is not exception. One of the new promising technology is the technology of 3D -printing of individual structures and buildings in general. 3Dprinting - is the process of real object recreating on the model of 3D. Unlike conventional printer which prints information on a sheet of paper, 3D-printer allows you to display three-dimensional information, i.e. creates certain physical objects. Currently, 3D-printer finds its application in many areas of production: machine building elements, a variety of layouts, interior elements, various items. But due to the fact that this technology is fairly new, it requires the creation of detailed and accurate technologies, efficient equipment and materials, and development of common vocabulary and regulatory framework in this field. Research Aim. The analysis of existing methods of creating physical objects using 3D-printing and the improvement of technology and equipment for the printing of buildings and structures. Conclusion. 3D-printers building is a new generation of equipment for the construction of buildings, structures, and structural elements. A variety of building printing technics opens up wide range of opportunities in the construction industry. At this stage, printers design allows to create low-rise buildings of different configurations with different mortars. The scientific novelty of this work is to develop proposals to improve the thermal insulation properties of constructed 3D-printing objects and technological equipment. The list of key terms and notions of construction

  9. A comparison of 4D time-resolved MRA with keyhole and 3D time-of-flight MRA at 3.0 T for the evaluation of cerebral aneurysms

    Wu Qian

    2012-07-01

    Full Text Available Abstract Background A subarachnoid hemorrhage (SAH due to the rupture of a cerebral aneurysm (CA is a devastating event associated with high rates of mortality. Magnetic resonance angiography (MRA, as a noninvasive technique, is typically used initially. The object of our study is to evaluate the feasibility of 4D time-resolved MRA with keyhole (4D-TRAK for the diagnostic accuracy and reliability of the detection and characterization of cerebral aneurysms (CAs, with a comparison of 3D time-of-flight MRA (3D-TOF-MRA by using DSA as a reference. Methods 3D-TOF-MRA, 4D-TRAK and 3D-DSA were performed sequentially in 52 patients with suspected CAs. 4D-TRAK was acquired using a combination of sensitivity encoding (SENSE and CE timing robust angiography (CENTRA k-space sampling techniques at a contrast dose of 10 ml at 3 T. Accuracy, sensitivity, specificity of 4D-TRAK and 3D-TOF-MRA were calculated and compared for the detection of CAs on patient-based and aneurysm-based evaluation using 3D-DSA as a reference. Results The overall image quality of 4D-TRAK with a contrast dose of 10 ml was in the diagnostic range but still cannot be compared with that of 3D-TOF-MRA. In 52 patients with suspected CAs, fifty-eight CAs were confirmed on 3D-DSA finally. Fifty-one (with 2 false-positives and 9 false-negatives and 58 (with 1 false-positive and 1 false-negative CAs were visualized on 4D-TRAK and 3D-TOF-MRA, respectively. Accuracy, sensitivity and specificity on patient-based evaluation of 4D-TRAK and 3D-TOF-MRA were 92.31%, 93.33%, 85.71% and 98.08%, 100%, 85.71%, respectively, and 74.07%, 75.00%, 66.67% and 96.30%, 95.83%, 100% on aneurysm-based evaluation in patients with multiple CAs, respectively. Subgroup analysis revealed that for 19 very small CAs (maximal diameter Conclusion 4D-TRAK at a lower contrast dose of 10 ml with a combination of SENSE and CENTRA at 3 T could provide similar diagnostic accuracy rate for CAs with maximal diameter ≥ 3 mm

  10. Spherical 3D Isotropic Wavelets

    Lanusse, F; Starck, J -L

    2011-01-01

    Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D Spherical Fourier-Bessel (SFB) analysis in is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the Fourier-Bessel decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. 2006. We also present a new fast Discrete Spherical Fourier-Bessel Transform (DSFBT) based on both a discrete Bessel Transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large...

  11. Improvement of 3D Scanner

    2003-01-01

    The disadvantage remaining in 3D scanning system and its reasons are discussed. A new host-and-slave structure with high speed image acquisition and processing system is proposed to quicken the image processing and improve the performance of 3D scanning system.

  12. 3D Printing for Bricks

    ECT Team, Purdue

    2015-01-01

    Building Bytes, by Brian Peters, is a project that uses desktop 3D printers to print bricks for architecture. Instead of using an expensive custom-made printer, it uses a normal standard 3D printer which is available for everyone and makes it more accessible and also easier for fabrication.

  13. 3D vision system assessment

    Pezzaniti, J. Larry; Edmondson, Richard; Vaden, Justin; Hyatt, Bryan; Chenault, David B.; Kingston, David; Geulen, Vanilynmae; Newell, Scott; Pettijohn, Brad

    2009-02-01

    In this paper, we report on the development of a 3D vision system consisting of a flat panel stereoscopic display and auto-converging stereo camera and an assessment of the system's use for robotic driving, manipulation, and surveillance operations. The 3D vision system was integrated onto a Talon Robot and Operator Control Unit (OCU) such that direct comparisons of the performance of a number of test subjects using 2D and 3D vision systems were possible. A number of representative scenarios were developed to determine which tasks benefited most from the added depth perception and to understand when the 3D vision system hindered understanding of the scene. Two tests were conducted at Fort Leonard Wood, MO with noncommissioned officers ranked Staff Sergeant and Sergeant First Class. The scenarios; the test planning, approach and protocols; the data analysis; and the resulting performance assessment of the 3D vision system are reported.

  14. PLOT3D user's manual

    Walatka, Pamela P.; Buning, Pieter G.; Pierce, Larry; Elson, Patricia A.

    1990-01-01

    PLOT3D is a computer graphics program designed to visualize the grids and solutions of computational fluid dynamics. Seventy-four functions are available. Versions are available for many systems. PLOT3D can handle multiple grids with a million or more grid points, and can produce varieties of model renderings, such as wireframe or flat shaded. Output from PLOT3D can be used in animation programs. The first part of this manual is a tutorial that takes the reader, keystroke by keystroke, through a PLOT3D session. The second part of the manual contains reference chapters, including the helpfile, data file formats, advice on changing PLOT3D, and sample command files.

  15. 3D printing in dentistry.

    Dawood, A; Marti Marti, B; Sauret-Jackson, V; Darwood, A

    2015-12-01

    3D printing has been hailed as a disruptive technology which will change manufacturing. Used in aerospace, defence, art and design, 3D printing is becoming a subject of great interest in surgery. The technology has a particular resonance with dentistry, and with advances in 3D imaging and modelling technologies such as cone beam computed tomography and intraoral scanning, and with the relatively long history of the use of CAD CAM technologies in dentistry, it will become of increasing importance. Uses of 3D printing include the production of drill guides for dental implants, the production of physical models for prosthodontics, orthodontics and surgery, the manufacture of dental, craniomaxillofacial and orthopaedic implants, and the fabrication of copings and frameworks for implant and dental restorations. This paper reviews the types of 3D printing technologies available and their various applications in dentistry and in maxillofacial surgery.

  16. Using 3D in Visualization

    Wood, Jo; Kirschenbauer, Sabine; Döllner, Jürgen

    2005-01-01

    The notion of three-dimensionality is applied to five stages of the visualization pipeline. While 3D visulization is most often associated with the visual mapping and representation of data, this chapter also identifies its role in the management and assembly of data, and in the media used...... to display 3D imagery. The extra cartographic degree of freedom offered by using 3D is explored and offered as a motivation for employing 3D in visualization. The use of VR and the construction of virtual environments exploit navigational and behavioral realism, but become most usefil when combined...... with abstracted representations embedded in a 3D space. The interactions between development of geovisualization, the technology used to implement it and the theory surrounding cartographic representation are explored. The dominance of computing technologies, driven particularly by the gaming industry...

  17. An integrated multidisciplinary re-evaluation of the geothermal system at Valles Caldera, New Mexico, using an immersive three-dimensional (3D) visualization environment

    Fowler, A.; Bennett, S. E.; Wildgoose, M.; Cantwell, C.; Elliott, A. J.

    2012-12-01

    We describe an approach to explore the spatial relationships of a geothermal resource by examining diverse geological, geophysical, and geochemical data sets using the immersive 3-dimensional (3D) visualization capabilities of the UC Davis Keck Center for Active Visualization in the Earth Sciences (KeckCAVES). The KeckCAVES is a facility where stereoscopic images are projected onto four, surfaces (three walls and a floor), which the user perceives as a seamless 3D image of the data. The user can manipulate and interact with the data, allowing a more intuitive interpretation of data set relationships than is possible with traditional 2-dimensional techniques. We incorporate multiple data sets of the geothermal system at Valles Caldera, New Mexico: topography, lithology, faults, temperature, alteration mineralogy, and magnetotellurics. With the ability to rapidly and intuitively observe data relationships, we are able to efficiently and rapidly draw conclusions about the subsurface architecture of the Valles Caldera geothermal system. We identify two high-temperature anomalies, one that corresponds with normal faults along the western caldera ring fracture, and one that with the resurgent dome. A cold-temperature anomaly identified adjacent to the resurgent dome high-temperature anomaly appears to relate to a fault controlled graben valley that acts as a recharge zone, likely funneling cold meteoric water into the subsurface along normal faults observed on published maps and cross sections. These high-temperature anomalies broadly correspond to subsurface regions where previous magnetotelluric studies have identified low apparent resistivity. Existing hot springs in the Sulfur Springs area correspond to the only location where our modeled 100°C isotherm intersects the ground surface. Correlation between the first occurrence of key alteration minerals (pyrite, chlorite, epidote) in previously drilled boreholes and our temperature model vary, with chlorite showing a

  18. Evaluating 3D printing to solve the sample-to-device interface for LRS and POC diagnostics: example of an interlock meter-mix device for metering and lysing clinical urine samples.

    Jue, Erik; Schoepp, Nathan G; Witters, Daan; Ismagilov, Rustem F

    2016-05-21

    This paper evaluates the potential of 3D printing, a semi-automated additive prototyping technology, as a means to design and prototype a sample-to-device interface, amenable to diagnostics in limited-resource settings, where speed, accuracy and user-friendly design are critical components. As a test case, we built and validated an interlock meter-mix device for accurately metering and lysing human urine samples for use in downstream nucleic acid amplification. Two plungers and a multivalve generated and controlled fluid flow through the device and demonstrate the utility of 3D printing to create leak-free seals. Device operation consists of three simple steps that must be performed sequentially, eliminating manual pipetting and vortexing to provide rapid (5 to 10 s) and accurate metering and mixing. Bretherton's prediction was applied, using the bond number to guide a design that prevents potentially biohazardous samples from leaking from the device. We employed multi-material 3D printing technology, which allows composites with rigid and elastomeric properties to be printed as a single part. To validate the meter-mix device with a clinically relevant sample, we used urine spiked with inactivated Chlamydia trachomatis and Neisseria gonorrhoeae. A downstream nucleic acid amplification by quantitative PCR (qPCR) confirmed there was no statistically significant difference between samples metered and mixed using the standard protocol and those prepared with the meter-mix device, showing the 3D-printed device could accurately meter, mix and dispense a human urine sample without loss of nucleic acids. Although there are some limitations to 3D printing capabilities (e.g. dimension limitations related to support material used in the printing process), the advantages of customizability, modularity and rapid prototyping illustrate the utility of 3D printing for developing sample-to-device interfaces for diagnostics.

  19. Evaluation of Infrared Images by Using a Human Thermal Model

    2001-10-25

    thermal environmental history have been recorded. In this case, the thermal environmental history could be estimated from the behavior of a subject... environmental history and physiological condition history. An advantage of the evaluation of IR images using the thermal model is to provide

  20. 40 CFR 90.427 - Catalyst thermal stress resistance evaluation.

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Catalyst thermal stress resistance... Gaseous Exhaust Test Procedures § 90.427 Catalyst thermal stress resistance evaluation. (a) The purpose of... catalyst conversion efficiency for Phase 1 engines. The thermal stress is imposed on the test catalyst...

  1. Spectroradiometric characterization of autostereoscopic 3D displays

    Rubiño, Manuel; Salas, Carlos; Pozo, Antonio M.; Castro, J. J.; Pérez-Ocón, Francisco

    2013-11-01

    Spectroradiometric measurements have been made for the experimental characterization of the RGB channels of autostereoscopic 3D displays, giving results for different measurement angles with respect to the normal direction of the plane of the display. In the study, 2 different models of autostereoscopic 3D displays of different sizes and resolutions were used, making measurements with a spectroradiometer (model PR-670 SpectraScan of PhotoResearch). From the measurements made, goniometric results were recorded for luminance contrast, and the fundamental hypotheses have been evaluated for the characterization of the displays: independence of the RGB channels and their constancy. The results show that the display with the lower angle variability in the contrast-ratio value and constancy of the chromaticity coordinates nevertheless presented the greatest additivity deviations with the measurement angle. For both displays, when the parameters evaluated were taken into account, lower angle variability consistently resulted in the 2D mode than in the 3D mode.

  2. Identification of curcumin derivatives as human glyoxalase I inhibitors: A combination of biological evaluation, molecular docking, 3D-QSAR and molecular dynamics simulation studies.

    Yuan, Minggui; Luo, Minxian; Song, Yao; Xu, Qiu; Wang, Xiaofeng; Cao, Yi; Bu, Xianzhang; Ren, Yanliang; Hu, Xiaopeng

    2011-02-01

    Several recent developments suggest that the human glyoxalase I (GLO I) is a potential target for anti-tumor drug development. In present study, a series of curcumin derivatives with high inhibitory activity against human GLO I were discovered. Inhibition constant (K(i)) values of compounds 8, 9, 10, 11 and 13 to GLO I are 4.600μM, 2.600μM, 3.200μM, 3.600μM and 3.600μM, respectively. To elucidate the structural features of potent inhibitors, docking-based three-dimensional structure-activity relationship (3D-QSAR) analyses were performed. Satisfactory agreement between experiment and theory suggests that comparative molecular similarity index analysis (CoMSIA) modeling exhibit much better correlation and predictive power. The cross-validated q(2) value is 0.638 while no-validation r(2) value is 0.930. Integrated with docking-based 3D-QSAR CoMSIA modeling, molecular surface property (electrostatic and steric) mapping and molecular dynamics simulation, a set of receptor-ligand binding models and bio-affinity predictive models for rational design of more potent inhibitors of GLO I are established.

  3. Development and evaluation of a new 3-D digitization and computer graphic system to study the anatomic tissue and restoration surfaces.

    Dastane, A; Vaidyanathan, T K; Vaidyanathan, J; Mehra, R; Hesby, R

    1996-01-01

    It is necessary to visualize and reconstruct tissue anatomic surfaces accurately for a variety of oral rehabilitation applications such as surface wear characterization and automated fabrication of dental restorations, accuracy of reproduction of impression and die materials, etc. In this investigation, a 3-D digitization and computer-graphic system was developed for surface characterization. The hardware consists of a profiler assembly for digitization in an MTS biomechanical test system with an artificial mouth, an IBM PS/2 computer model 70 for data processing and a Hewlett-Packard laser printer for hardcopy outputs. The software used includes a commercially available Surfer 3-D graphics package, a public domain data-fitting alignment software and an inhouse Pascal program for intercommunication plus some other limited tasks. Surfaces were digitized before and after rotation by angular displacement, the digital data were interpolated by Surfer to provide a data grid and the surfaces were computer graphically reconstructed: Misaligned surfaces were aligned by the data-fitting alignment software under different choices of parameters. The effect of different interpolation parameters (e.g. grid size, method of interpolation) and extent of rotation on the alignment accuracy was determined. The results indicate that improved alignment accuracy results from optimization of interpolation parameters and minimization of the initial misorientation between the digitized surfaces. The method provides important advantages for surface reconstruction and visualization, such as overlay of sequentially generated surfaces and accurate alignment of pairs of surfaces with small misalignment.

  4. Scoops3D: software to analyze 3D slope stability throughout a digital landscape

    Reid, Mark E.; Christian, Sarah B.; Brien, Dianne L.; Henderson, Scott T.

    2015-01-01

    The computer program, Scoops3D, evaluates slope stability throughout a digital landscape represented by a digital elevation model (DEM). The program uses a three-dimensional (3D) method of columns approach to assess the stability of many (typically millions) potential landslides within a user-defined size range. For each potential landslide (or failure), Scoops3D assesses the stability of a rotational, spherical slip surface encompassing many DEM cells using a 3D version of either Bishop’s simplified method or the Ordinary (Fellenius) method of limit-equilibrium analysis. Scoops3D has several options for the user to systematically and efficiently search throughout an entire DEM, thereby incorporating the effects of complex surface topography. In a thorough search, each DEM cell is included in multiple potential failures, and Scoops3D records the lowest stability (factor of safety) for each DEM cell, as well as the size (volume or area) associated with each of these potential landslides. It also determines the least-stable potential failure for the entire DEM. The user has a variety of options for building a 3D domain, including layers or full 3D distributions of strength and pore-water pressures, simplistic earthquake loading, and unsaturated suction conditions. Results from Scoops3D can be readily incorporated into a geographic information system (GIS) or other visualization software. This manual includes information on the theoretical basis for the slope-stability analysis, requirements for constructing and searching a 3D domain, a detailed operational guide (including step-by-step instructions for using the graphical user interface [GUI] software, Scoops3D-i) and input/output file specifications, practical considerations for conducting an analysis, results of verification tests, and multiple examples illustrating the capabilities of Scoops3D. Easy-to-use software installation packages are available for the Windows or Macintosh operating systems; these packages

  5. ADT-3D Tumor Detection Assistant in 3D

    Jaime Lazcano Bello

    2008-12-01

    Full Text Available The present document describes ADT-3D (Three-Dimensional Tumor Detector Assistant, a prototype application developed to assist doctors diagnose, detect and locate tumors in the brain by using CT scan. The reader may find on this document an introduction to tumor detection; ADT-3D main goals; development details; description of the product; motivation for its development; result’s study; and areas of applicability.

  6. Micro-Climate Evaluation System in Thermal Mines

    2006-01-01

    A fuzzy evaluation method was used to evaluate the microclimate in thermal mines. A theoretical model of a microclimate evaluation system was designed and membership functions of the evaluation indices in the system were established. An analytical hierarchy process (AHP) was used to analyze the weight of the evaluation indices and their methods of calculation. Software for this evaluation system was developed and used for the evaluation of the microclimate of 714 sections in a mine. It is shown that the evaluation results correspond completely with the actual situation. This evaluation system and the software can be applied in thermal mines.

  7. Thermal fatigue of composites: Ultrasonic and SEM evaluations

    Forsyth, D.S.; Kasap, S.O. (Univ. of Saskatchewan, Saskatoon (Canada). Dept. of Electrical Engineering); Wacker, I.; Yannacopoulos, S. (Univ. of Saskatchewan, Saskatoon (Canada). Dept. of Mechanical Engineering)

    1994-01-01

    Results are presented on the evaluation of thermal fatigue in three fiber reinforced polymer composites, using ultrasonic techniques and scanning electron microscopy. The composites examined were (a) continuous carbon fibers in a vinylester matrix (b) continuous aramid fibers in a vinylester matrix and (c) randomly oriented aramid fibers in a polyphenylene matrix. Specimens of these composites were subjected to thermal fatigue by thermal cycling from [minus]25 C to 75 C. Changes in ultrasonic attenuation and velocity were monitored during thermal cycling, and scanning electron microscopy was used to qualitatively evaluate any damage. It was observed that ultrasonic attenuation is sensitive to thermal fatigue, increasing with increasing number of thermal cycles. SEM evaluations showed that the primary damage due to thermal fatigue is due to fiber-matrix debonding.

  8. Bioprinting of 3D hydrogels.

    Stanton, M M; Samitier, J; Sánchez, S

    2015-08-07

    Three-dimensional (3D) bioprinting has recently emerged as an extension of 3D material printing, by using biocompatible or cellular components to build structures in an additive, layer-by-layer methodology for encapsulation and culture of cells. These 3D systems allow for cell culture in a suspension for formation of highly organized tissue or controlled spatial orientation of cell environments. The in vitro 3D cellular environments simulate the complexity of an in vivo environment and natural extracellular matrices (ECM). This paper will focus on bioprinting utilizing hydrogels as 3D scaffolds. Hydrogels are advantageous for cell culture as they are highly permeable to cell culture media, nutrients, and waste products generated during metabolic cell processes. They have the ability to be fabricated in customized shapes with various material properties with dimensions at the micron scale. 3D hydrogels are a reliable method for biocompatible 3D printing and have applications in tissue engineering, drug screening, and organ on a chip models.

  9. Thermal fluid mixing behavior during medium break LOCA in evaluation of pressurized thermal shock

    Jung, Jae Won; Bang, Young Seok; Seul, Kwang Won; Kim, Hho Jung [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    1998-12-31

    Thermal fluid mixing behavior during a postulated medium-size hot leg break loss of coolant accident is analyzed for the international comparative assessment study on pressurized thermal shock (PTS-ICAS) proposed by OECD-NEA. The applicability of RELAP5 code to analyze the thermal fluid mixing behavior is evaluated through a simple modeling relevant to the problem constraints. Based on the calculation result, the onset of thermal stratification is investigated using Theofanous`s empirical correlation. Sensitivity calculations using a fine node model and crossflow model are also performed to evaluate the modeling capability on multi-dimensional characteristics related to thermal fluid mixing. 6 refs., 8 figs. (Author)

  10. Tuotekehitysprojekti: 3D-tulostin

    Pihlajamäki, Janne

    2011-01-01

    Opinnäytetyössä tutustuttiin 3D-tulostamisen teknologiaan. Työssä käytiin läpi 3D-tulostimesta tehty tuotekehitysprojekti. Sen lisäksi esiteltiin yleisellä tasolla tuotekehitysprosessi ja syntyneiden tulosten mahdollisia suojausmenetelmiä. Tavoitteena tässä työssä oli kehittää markkinoilta jo löytyvää kotitulostin-tasoista 3D-laiteteknologiaa lähemmäksi ammattilaistason ratkaisua. Tavoitteeseen pyrittiin keskittymällä parantamaan laitteella saavutettavaa tulostustarkkuutta ja -nopeutt...

  11. Handbook of 3D integration

    Garrou , Philip; Ramm , Peter

    2014-01-01

    Edited by key figures in 3D integration and written by top authors from high-tech companies and renowned research institutions, this book covers the intricate details of 3D process technology.As such, the main focus is on silicon via formation, bonding and debonding, thinning, via reveal and backside processing, both from a technological and a materials science perspective. The last part of the book is concerned with assessing and enhancing the reliability of the 3D integrated devices, which is a prerequisite for the large-scale implementation of this emerging technology. Invaluable reading fo

  12. Color 3D Reverse Engineering

    2002-01-01

    This paper presents a principle and a method of col or 3D laser scanning measurement. Based on the fundamental monochrome 3D measureme nt study, color information capture, color texture mapping, coordinate computati on and other techniques are performed to achieve color 3D measurement. The syste m is designed and composed of a line laser light emitter, one color CCD camera, a motor-driven rotary filter, a circuit card and a computer. Two steps in captu ring object's images in the measurement process: Firs...

  13. Exploration of 3D Printing

    Lin, Zeyu

    2014-01-01

    3D printing technology is introduced and defined in this Thesis. Some methods of 3D printing are illustrated and their principles are explained with pictures. Most of the essential parts are presented with pictures and their effects are explained within the whole system. Problems on Up! Plus 3D printer are solved and a DIY product is made with this machine. The processes of making product are recorded and the items which need to be noticed during the process are the highlight in this th...

  14. Synthesis of novel trifluoromethyl-substituted spiro-[chromeno[4,3-d]pyrimidine-5,1'-cycloalkanes], and evaluation of their analgesic effects in a mouse pain model.

    Bonacorso, Helio G; Rosa, Wilian C; Oliveira, Sara M; Brusco, Indiara; Brum, Evelyne S; Rodrigues, Melissa B; Frizzo, Clarissa P; Zanatta, Nilo

    2017-04-01

    Herein we report the synthesis of twelve 2,5-substituted 4-(trifluoromethyl)-spirochromeno[4,3-d]pyrimidines (7-10), as well as an evaluation of their analgesic effect in a mouse pain model. The nine new chromeno[4,3-d]pyrimidines (7-9) were synthesized from the cyclocondensation reactions of three 2,2,2-trifluoro-1-(4-methoxyspiro[chromene-2,1'-cycloalkane]-3-yl)ethanones (3) containing 5-, 6- and 7-membered spirocycloalkanes, with some well-known amidine salts (4-6) [NH2CR(NH)]-in which R=Me, Ph, and NH2-at yields of 60-95%. Subsequently, three new 2-(pyrrol-1-yl)-4-(trifluoromethyl)-chromeno[4,3-d]pyrimidines (10) were obtained through a Clauson-Kaas reaction between the respective 2-(amino)-4-(trifluoromethyl)-chromeno[4,3-d]pyrimidines (9) and 2,5-dimethoxy-tetrahydrofuran. The analgesic evaluation showed that these 4-(trifluoromethyl)chromeno[4,3-d]pyrimidines (100mg/kg, p.o.) and Ketoprofen (100mg/kg, p.o.) significantly reduced capsaicin-induced spontaneous nociception. Moreover, the 2-pyrrolyl-spirocyclohexane derivative 10b (100 and 300mg/kg, p.o.) had an anti-allodynic effect comparable to Ketoprofen (100 and 300mg/kg, p.o.) in the arthritic pain model, without causing locomotor alterations in the mice. These results suggest that the compound 10b is a promising molecule for new analgesic drugs in the treatment of pathological pain, such as in arthritis.

  15. 视频立体增强现实系统舒适度评价方法研究%Study on Video 3D AR Systems Comfort Evaluation Method

    李壮恒; 王涌天; 翁冬冬

    2012-01-01

    The evaluation of the effectiveness of stereo images ss a hot issue. Many researchers made intensive studies of this. However, few researches are focused on the 3D effects of 3D augmented reality system. In this paper we studied on Comfort Level Evaluation in see - through 3D augmented reality systems. We designed three experiments for the analysis the factors that impact the comfort level of see - through 3D augmented reality systems. The experiments show that the matching of virtual camera and real camera parameters affects the comfort level. This paper has a certain reference value for 3D augmented reality system design.%立体图像效果的评价是一个热点问题,许多文献对此进行了深入的探讨.但是,对于立体增强现实系统的立体效果进行研究的文献比较少,针对视频透射式立体增强现实系统,对其舒适度进行了研究,设计了三个实验并对影响立体增强现实系统虚实融合效果的因素进行分析.实验表明虚拟摄像机与实景摄像机参数的匹配程度对最终的舒适度具有影响.对于立体增强现实系统的设计具有一定参考价值.

  16. Development and evaluation of a LOR-based image reconstruction with 3D system response modeling for a PET insert with dual-layer offset crystal design

    Zhang, Xuezhu; Stortz, Greg; Sossi, Vesna; Thompson, Christopher J.; Retière, Fabrice; Kozlowski, Piotr; Thiessen, Jonathan D.; Goertzen, Andrew L.

    2013-12-01

    In this study we present a method of 3D system response calculation for analytical computer simulation and statistical image reconstruction for a magnetic resonance imaging (MRI) compatible positron emission tomography (PET) insert system that uses a dual-layer offset (DLO) crystal design. The general analytical system response functions (SRFs) for detector geometric and inter-crystal penetration of coincident crystal pairs are derived first. We implemented a 3D ray-tracing algorithm with 4π sampling for calculating the SRFs of coincident pairs of individual DLO crystals. The determination of which detector blocks are intersected by a gamma ray is made by calculating the intersection of the ray with virtual cylinders with radii just inside the inner surface and just outside the outer-edge of each crystal layer of the detector ring. For efficient ray-tracing computation, the detector block and ray to be traced are then rotated so that the crystals are aligned along the X-axis, facilitating calculation of ray/crystal boundary intersection points. This algorithm can be applied to any system geometry using either single-layer (SL) or multi-layer array design with or without offset crystals. For effective data organization, a direct lines of response (LOR)-based indexed histogram-mode method is also presented in this work. SRF calculation is performed on-the-fly in both forward and back projection procedures during each iteration of image reconstruction, with acceleration through use of eight-fold geometric symmetry and multi-threaded parallel computation. To validate the proposed methods, we performed a series of analytical and Monte Carlo computer simulations for different system geometry and detector designs. The full-width-at-half-maximum of the numerical SRFs in both radial and tangential directions are calculated and compared for various system designs. By inspecting the sinograms obtained for different detector geometries, it can be seen that the DLO crystal

  17. Synthesis, biological evaluation and 3D-QSAR studies of novel 4,5-dihydro-1H-pyrazole niacinamide derivatives as BRAF inhibitors.

    Li, Cui-Yun; Li, Qing-Shan; Yan, Li; Sun, Xiao-Guang; Wei, Ran; Gong, Hai-Bin; Zhu, Hai-Liang

    2012-06-15

    A series of novel 4,5-dihydropyrazole derivatives containing niacinamide moiety as potential V600E mutant BRAF kinase (BRAF(V600E)) inhibitors were designed and synthesized. Results of the bioassays against BRAF(V600E) and WM266.4 human melanoma cell line showed several compounds to be endowed potent activities with IC(50) and GI(50) value in low micromolar range, among which compound 27e, (5-(4-Chlorophenyl)-3-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl)6-methylpyridin-3-yl methanone (IC(50)=0.20 μM, GI(50)=0.89 μM) was bearing the best bioactivity comparable with the positive control Sorafenib. Docking simulation was performed to determine the probable binding model and 3D-QSAR model was built to provide more pharmacophore understanding that could use to design new agents with more potent BRAF(V600E) inhibitory activity.

  18. Establishment of a heterotypic 3D culture system to evaluate the interaction of TREG lymphocytes and NK cells with breast cancer.

    Augustine, Tanya N; Dix-Peek, Thérèse; Duarte, Raquel; Candy, Geoffrey P

    2015-11-01

    Three-dimensional (3D) culture approaches to investigate breast tumour progression are yielding information more reminiscent of the in vivo microenvironment. We have established a 3D Matrigel system to determine the interactions of luminal phenotype MCF-7 cells and basal phenotype MDA-MB-231 cells with regulatory T lymphocytes and Natural Killer cells. Immune cells were isolated from peripheral blood using magnetic cell sorting and their phenotype validated using flow cytometry both before and after activation with IL-2 and phytohaemagglutinin. Following the establishment of the heterotypic culture system, tumour cells displayed morphologies and cell-cell associations distinct to that observed in 2D monolayer cultures, and associated with tissue remodelling and invasion processes. We found that the level of CCL4 secretion was influenced by breast cancer phenotype and immune stimulation. We further established that for RNA extraction, the use of proteinase K in conjunction with the Qiagen RNeasy Mini Kit and only off-column DNA digestion gave the best RNA yield, purity and integrity. We also investigated the efficacy of the culture system for immunolocalisation of the biomarkers oestrogen receptor-α and the glycoprotein mucin 1 in luminal phenotype breast cancer cells; and epidermal growth factor receptor in basal phenotype breast cancer cells, in formalin-fixed, paraffin-wax embedded cultures. The expression of these markers was shown to vary under immune mediation. We thus demonstrate the feasibility of using this co-culture system for downstream applications including cytokine analysis, immunolocalisation of tumour biomarkers on serial sections and RNA extraction in accordance with MIQE guidelines.

  19. Image quality assessment of LaBr{sub 3}-based whole-body 3D PET scanners: a Monte Carlo evaluation

    Surti, S [Department of Radiology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Karp, J S [Department of Radiology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Muehllehner, G [Philips Medical Systems, Philadelphia, PA 19104 (United States)

    2004-10-07

    The main thrust for this work is the investigation and design of a whole-body PET scanner based on new lanthanum bromide scintillators. We use Monte Carlo simulations to generate data for a 3D PET scanner based on LaBr{sub 3} detectors, and to assess the count-rate capability and the reconstructed image quality of phantoms with hot and cold spheres using contrast and noise parameters. Previously we have shown that LaBr{sub 3} has very high light output, excellent energy resolution and fast timing properties which can lead to the design of a time-of-flight (TOF) whole-body PET camera. The data presented here illustrate the performance of LaBr{sub 3} without the additional benefit of TOF information, although our intention is to develop a scanner with TOF measurement capability. The only drawbacks of LaBr{sub 3} are the lower stopping power and photo-fraction which affect both sensitivity and spatial resolution. However, in 3D PET imaging where energy resolution is very important for reducing scattered coincidences in the reconstructed image, the image quality attained in a non-TOF LaBr{sub 3} scanner can potentially equal or surpass that achieved with other high sensitivity scanners. Our results show that there is a gain in NEC arising from the reduced scatter and random fractions in a LaBr{sub 3} scanner. The reconstructed image resolution is slightly worse than a high-Z scintillator, but at increased count-rates, reduced pulse pileup leads to an image resolution similar to that of LSO. Image quality simulations predict reduced contrast for small hot spheres compared to an LSO scanner, but improved noise characteristics at similar clinical activity levels.

  20. Evaluation of the diagnostic efficiency and application value of MRI 3D-SPACE and VIBE sequence on trigeminal microvascular oppression%评价磁共振3D-SPACE序列及VIBE序列对三叉神经微血管压迫的诊断效能及应用价值

    班秀丽; 程志才

    2014-01-01

    目的:探讨磁共振3D-SPACE及VIBE序列对三叉神经微血管压迫的诊断效能及实际应用价值。方法:对18例单侧原发性三叉神经痛患者同时行磁共振3D-SPACE 及 VIBE 序列检查,所有患者均经三叉神经微血管减压术证实。分析三叉神经微血管压迫的影像学特征,评价其显示三叉神经脑池段与周围血管关系的能力和优势。结果:18例患者中,症状侧血管神经Ⅰ型3例(16.6%),Ⅱ型12例(66.6%),Ⅲ型3例(16.6%);而无症状侧Ⅰ型12例(66.7%),Ⅱ型6例(33.3%),Ⅲ型0例;双侧压迫程度差异显著,有统计学意义(P=0.000)。在有血管神经接触、压迫情况的神经中,症状侧15例中近端压迫9例,远端压迫6例;无症状侧6例中近端压迫4例,远端压迫2例,症状侧与非症状侧压迫点位置差异无统计学意义(P=0.328)。症状侧小脑上动脉为主要接触、压迫血管(58%)。3D-SPACE及VIBE序列能对三叉神经进行多平面重建,显示血管压迫三叉神经的位置、程度及责任血管的来源。结论:3D-SPACE序列能清晰显示三叉神经与周围结构的关系,VIBE序列是三叉神经MR成像常用的补充序列,3D-SPACE与VIBE序列相结合能提供准确的诊断信息,对原发性三叉神经痛的诊断具有重要价值。%Objective:To explore the diagnostic efficiency and practical application value of MRI 3D-SPACE and VIBE sequence on trigeminal microvascular oppression.Methods:18 patients with unilateral primary trigeminal neuralgia were given MR 3D-SPACE and VIBE sequence checking.All patients were confirmed by microvascular decompression of the trigeminal nerve. The imaging characteristics of trigeminal microvascular oppression were analyzed.The ability and advantage of showing the relationship between trigeminal nerve brain pool and surrounding blood-vessel were evaluated.Results:In 18 patients,3 cases(16.6% ) were symptoms Ⅰ type lateral neurovascular

  1. Accepting the T3D

    Rich, D.O.; Pope, S.C.; DeLapp, J.G.

    1994-10-01

    In April, a 128 PE Cray T3D was installed at Los Alamos National Laboratory`s Advanced Computing Laboratory as part of the DOE`s High-Performance Parallel Processor Program (H4P). In conjunction with CRI, the authors implemented a 30 day acceptance test. The test was constructed in part to help them understand the strengths and weaknesses of the T3D. In this paper, they briefly describe the H4P and its goals. They discuss the design and implementation of the T3D acceptance test and detail issues that arose during the test. They conclude with a set of system requirements that must be addressed as the T3D system evolves.

  2. Advanced 3-D Ultrasound Imaging

    Rasmussen, Morten Fischer

    The main purpose of the PhD project was to develop methods that increase the 3-D ultrasound imaging quality available for the medical personnel in the clinic. Acquiring a 3-D volume gives the medical doctor the freedom to investigate the measured anatomy in any slice desirable after the scan has...... been completed. This allows for precise measurements of organs dimensions and makes the scan more operator independent. Real-time 3-D ultrasound imaging is still not as widespread in use in the clinics as 2-D imaging. A limiting factor has traditionally been the low image quality achievable using...... Field II simulations and measurements with the ultrasound research scanner SARUS and a 3.5MHz 1024 element 2-D transducer array. In all investigations, 3-D synthetic aperture imaging achieved a smaller main-lobe, lower sidelobes, higher contrast, and better signal to noise ratio than parallel...

  3. Conducting polymer 3D microelectrodes

    Sasso, Luigi; Vazquez, Patricia; Vedarethinam, Indumathi

    2010-01-01